Major ouch

Ok, final table..blinds of 100/200 first hand, I look down at 9-3 offsuit on my small blind I call w/ no raisers... flop 9-9-J... rainbow.. bet of 600, call, I think, "ok, there is only one nine left, somebody could be on a draw" so I just flat call, BB shoves all in for like 7 grand..bout what I have..ultimately I fold...turned out we had the same hand.....

two hands later....I look down at k/5....crap hand, but I limp...heads up..(kings had been hot all day) flop comes K-Q-9 all hearts, i bet 600 out, guy calls, turn comes 7, I bet 600 guy calls, river another king...I check, guy shoves and has me covered..Ive seen how this guy has played all day I think "well he wouldnt slow play a flush, or the nut straight with a possible flush draw, he wouldnt have limped with ace king" I call and he flips over king-queen......ouch...