You'll get there...just takes time. Lets go a over a few things:
The airstill: those things run with continuous heat until you shut them off. You have to know when your run of wash/mash/low-wines is done and pull the plug on it. Otherwise, it will just run all the alcohol out, then start putting water in it...eventually, you'd just end up with what you started with. That's probably how you ended up with only 10%. Your wash was probably close to that when you started. It's a common misconception starting out that 1 gal of mash/low-wines makes 1 gal of booze. Doesn't work like that. The still doesn't "make" alc. The fermentation makes the alc, and the distillation "concentrates" the alc by separating it from the water based mixture based on differing boiling points. So, 4,000ml (1L) of 10% wash...has a potential of 400ml (1,000 x .10) of 100% alc that you can possibly extract. The way to look at it is..it's the "same" amount of alc only concentrated in different volumes. This is also the reason that those tiny volume stills are difficult to do cuts on...(because you actually get so little back and you'd have to collect in very small amounts to even notice transitions.
The next thing I think is to talk about your still. Can you post a pic so we can see what your working with here? Did you follow the basic boka plans? I just want to double check a couple things here...you say it's 24" (2 feet) and your plates are halfway (or 12") and your condenser fits in the top half. I think your build is a little off if that's the case. Your condenser should only be about 6" long or so. And the top plate should only be about 1" below the bottom of the coil. It's ok if your condenser is longer (it's just overkill), BUT, the important part is your top plate should "still" start only 1" below the bottom of it ....which basically means you'd need an even "longer" column/tube to start with — hence the reason most people build them more compact...to allow more room for packing in the tube and avoid excess column height/weight. So, unless your condenser is 12" long, your plates are far to low. If that's the case its easy enough to fix. Just trim the top of the column down till the coil sits at the proper height. Then, you are gonna need a longer tube "below" for more packing. Cut, the pipe several" below the plates/take-off, and add another length of pipe using a copper join to solder the bottom part with your connection on it to your pot, to the top part with plates. Measure twice, cut once, to achieve the proper length you need for packing...which is measured from a couple inches inside the column, up to a 2 or 3 inches below the "bottom" plate.
The packing should be 24-36" with most people opting for the later making a taller column, which makes it easier to squeeze out the last few % between 93-95%. My column is short at 36" and has a 6" condenser, and uses about 24-26" of copper mesh packing rolled up in it and it easily hits 93%. But, I'd have to really work hard to get past that (ie., let it equalize a really long time and drip it off very slowly). So, if you want to build it proper...you need about 40" of pipe between your pot and the bottom plate to accommodate 36" of packing plus leaving room for a couple inches each side....(the plates/coil being above that and requiring even further/more length). If height or weight is a concern, you can make is shorter but it's going to come at the expense of having to work harder (slower) to push it up to azetrope (and may or may not even reach that if you cut too short). I think the absolute min would be about 24-26".....which is what I have. If your column/packing is too short...you'll find it very hard to hold a stable temp in there. The other thing to help with that is also to insulate the column. I use black-foamrubber looking stuff thats actually made for insulating pipes from "cold" but it works fine. It's pre-cut for size and has tape/glue on one side. I put zip-ties around it top and bottom to keep it from coming off.
Cuts: this is something that you'll gain experience with over time. But, you are doing the right thing by using your own senses to detect the various fractions. You may have stopped early....need more info to determine that. What you do is multiply your volume, by the %abv which will give you the total of 100% alc available. That's theoretical number given its not possible to collect 100%, but it's close enough to give us an idea of how much total volume to expect. You also aren't going to be collecting down to "zero" either as the amount of fuel/energy/time it would take to push out the last bit of alc would not warrant what you'd get back. Overall volume will fluctuate based on proof as well.
The higher the proof, the more concentrated the E02 is, the less flavor will be imparted via the various compounds. Sounds like you already notice the heads. You should be "tasting" as well. Watering down higher proof to about 40% or so will usually bring out the off flavors even more. But, you should at least drip it on your finger and taste it as it comes out now and again. Heads are sweet as they are very high concentration of alc, and have a solvent taste to them and often smell of fingernail polish. That fades..both in smell and taste, until it's clean. Then a very "different" taste will start to fade "in" (tails). It's hard to describe, but has been described many ways...wetcardboard smell/taste, wet dog, burned taste, etc. To me it has a "bourbon" like flavor to it early on...and gets rather nasty — particularly at higher proofs. Very rough/bitter and base tasting...before finally fading out as it turns to water. So, a couple points here...one is...you need to taste. You'll taste tails before you smell them. By the time you smell them...it's a little late. And the other is to note that potstill distillation is linear and starts at it's highest abv...and ends lowest. Reflux stills attempt to flatten that curve in the middle...by "holding" higher abv...for longer...before suddenly dropping off right at the end.
A good way to learn about various fractions is to collect everything that comes out in multiple jars. Try to use at least 12-15. Divide your total volume you figured earlier by the number of jars to know how much to collect in each. Then line them up and smell, taste them. Another thing to do is to use a parrot...and float your hydrometer to monitor the abv constantly throughout your run. You'll start to see a correlation between vapor/column temp and abv. As temps go up, proof goes down, and visa-versa. If you'r doing a run on a boka under reflux and suddenly the temp starts to go up...that's a sure sign you are approaching tails. I usually close the valve again at that point and let it equalize again for a while. That will bring the temp back to where it was.
Anyway, other than an equipment check here...sounds like you just need more practice thats all. You'll get there
. That's what I thought of as low wines. I guess not as the hydrometer only showed them sitting at about 10% or 20 proof. 
Does that sound correct? 
It has an interesting "malty" bran like nose and flavor, not heavy or overwhelming but smooth and subtle. There's a nice kick and burn to the undiluted spirit. I'm sure with diligent aging in a properly charred cask this batch would be AWESOME!! 
"Hon....where's those extra boxes of Corn Flakes?" 