i played bad

[johnsy]

5-10nl ...very loose play from more than 1/2 the table(K9, j5 being regulary played for 30-50$ rasies).....stack sizes vary i cant remember all of them..........Hero has @800.........6 limpers....hero has As7s on button and calls......Flop Kd6s6c.......check around.......turn 10s......HERE IS WHERE I MADE A HUGE MISTAKE....BB bets $30....he has me covered(i thought he was UTG(this comes into play later)).....2 callers ....hero calls...thought it was a close call but correct with implied odds....river 4s......BB(who i still thought was under the gun) bets $200....2 limpers fold....i push

Now after reviewing my play i realize that my river play was much 2 aggresive......i put the villan(bb) on a six with no kicker(BECAUSE I THOUGHT HE WAS UTG), and didnt see how he could have filled up.......but other than the obviously bad river play, did i misplay this hand on other streets? or even preflop? any comments, suggestions......thanks