Hero +1 UTG 200 Euro(AAJ3)

Rest off table Covers Hero

Hero raise 7.5(Did this raise hand before and folded to a 4-bet to 30 hoped somebody noticed that.)

Next player raise 12.5(guess he wanted to build pot find out if I had aces?) 4 other callers

Hero Calls, perhaps my first mistake but potting here would make the pot about 80. And people live DO NOT LIKE to fold after they put initial money so i expect to get 3-4 callers anyway. Should I do it here and get 40% off my stack in and then jam 90% of flops?(Seems like a variance heavy line)

Flop AT9 Rainbow 2 People X

Hero? I could X and hope somebody will take a stab at the pot, its unlikely as people like to X/C with their draws since fearing a X/R. I also block 3 Aces meaning AT,A9 combos are less and alot off people just X T9 here. 

If somebody has 99,TT they are GONNA 3-bet me anyway meaning they will isolate me against other draws which is exactly what I want. Problem is if people dont have any decent made hand here they are just X behind or calling my raise. I still want to build a pot if a safe turn cards comes or board pares.  But betting FULL POT people will just call and I would commit so much off my stack it feels its a mistake to fold almost any turns cause off odds.

I decided to bet 40 here leaving me for about a pot sized bet on the turn if I got 2 callers. Wrong or right?