Rookie spirit run

[Cliffie68]

I have a three gallon stainless steel pot still. I am using sugar, water and yeast to make 6.5 gallons of mash. I am producing about 5 quarts of clear liquid (heads, hearts and tails) which distills at about 186 degrees. (ranging from 40-74% abv) After a few first runs, I collected about 3 gallons of the heads, hearts and tails, I put it all back in the still to distill it again. The liquid produced 3 quarts of clear liquid at 174 degrees, and then began to get hotter. The condensing tube started shooting out steam very rapidly and I had to turn the heat off. I tried to reheat the liquid, but the same thing happened. The 3 quarts that I did yield, tested at about 86-90% abv. But I was unable to distill any more liquid from the pot because it was boiling over.
My questions:
#1 is there a way for me to extract more drinkable liquid from what is in the pot?
#2 will there be any added benefit to adding the leftover clear liquid to my next run?

Any advice or suggestions?