Hey guys, unsure if I made the correct call here. blinds $0.20/$0.40


Dealt to hero (mp) [Ts Ah]
fold,fold
hero raises to $1.20 from mp
fold
CO calls $1.20
button calls $1.20
sb calls $1.20
bb folds

This may be my first mistake, maybe I should not be opening ATo in from this position. People in this game tend to get sticky with their aces though so I think I am ahead of most people's calling range and just fold to a 3bet. I should be able to get 2 streets of value quite easily from weaker aces if I do hit.

** Flop ** [6d 2d 5h] (pot $5 ish)
checks through

Wet-ish board, doesn't hit my range at all as pre flop raiser. I figure that someone must have a set/pair+straight draw/FD on this board so I don't think betting into 4 people is wise.
I would expect hands like A6 and A5 to bet for protection, and straights to bet for value here. After it checks through I don't think anyone has top pair, nor do I think anyone has a straight.

** Turn ** [Qs] (pot $5 ish)
checks through

Similar reasoning as before, I don't think bluffing into 4 people is the right play here. After it checks through again I think I can eliminate flush draws from people's range (I expect them to have bet the flop or at least the turn) since there is a good chance to pick up the pot with a FD with a bet since everyone checked flop.

** River ** [Ad] (pot $5 ish)
board: [6d 2d 5h Qs Ad]

SB bets $3.20
hero calls $3.20
CO raises to $14.00
fold,fold
hero ???

Here, I think calling the SB bet is pretty standard. AJ+ probably 3bets pre (especially from sb), A6 would have bet flop. We beat A3/A4 (which may have bet flop/turn with a gutshot), and A7-A9. I expect SB to bet with these hands so I make the call. When CO raises I am a bit worried. I dont expect him to have a flush here since he would have surely bet flop or turn with those. Same goes for sets which would have bet earlier for value. I also dont think that he has AJ+ since those would 3-bet pre. I think the only value hands that he raises here are A2 and maybe A5 (two pair hands with a Q would have bet turn).
He could be trying to take the pot down with a bluff by means of a polarized bet since he expects SB and myself to be weak considering we checked 2 streets.

What would you guys do here? I feel a bit unsure about AJ actually. Not everybody 3bets AJ pre so maybe that should be what makes me fold here.

Also, I am really trying to improve my game and what I stated above is more or less my thought process throughout a hand. Please let me know if you think my general thought process is flawed in a way since I would like to improve my overall poker-thinking.