Live game 1/2, 7 handed with one big fish on the table, the game was just warming up.

Utg straddle4,3callers, hero was button had 200stake wake up with Ah Kd, raise to 22, small blind 3bet to 50, with about 500left, small blind was a TAG, i was preaty sure i was beat, his range was so polarized AK at least AA, kk,qq,or ak,jj 1010 are not likely, I had position, so i called.

Flop comes Ac Qh 3d,

small blind leads out 200,put me allin. Holy crap! that was i was thinking. why would you bet so much if you really had a set on such a dry board? so the only hand i could beat was KK and chop with AK. Will he bet so much with kk on that board? no way! AK maybe? possible,aa,qq is possible but not likely!it's just the question why so much was killing me! i couldnt convince me of folding,

 so i called and he showed me aa.