30-60 Hand, Someone elses mistake cost me a big pot(I think!)

[Jacob]

30-60, 10 handed. I am UTG. See AdAh. Raise. MP calls, CO+1 calls, CO calls, blinds call.

Not a good sign. Too many people.

Flop Jc7c2h. I think its a pretty safe flop. I bet. CO+1 raises(???).Flush draw maybe. AJ maybe(he would raise on both those hands). CO calls.(I am not sure what he has. Maybe set of 7s).

Turn 3c. I check. CO+1 bets, CO calls. I still put CO+1 on a draw(just by experience playing with him). Coudnt put CO on a hand. If he had a set I think he would have raised.

River 3h. I check. CO+1 checks(????, missed flush), CO bets. How did the 3 help him??. I coudnt put him on a hand. There was $760 in the put. I decided to call. CO+1 disappointingly says You are calling. Thinks about it and mucks his hand.

CO shows 22 for a full house and drags the pot.

I was a little upset and asked CO+1 what did he have. Wtf... Why didnt you 3 bet. There is no way CO would have called $90 with a pair of 2s.

What did CO+1 have and is my frustration justified?


Thanks,
Jacob