$.02/.04 Online 4 Players
Effective Stack Size: $3.50

Hero is in CO with AhAc.
Hero raises to $.12. BU calls. SB calls.

Pot: $.40
Flop: 2s2hQc
SB checks. Hero checks. BU bets $.40. SB folds. Hero calls.

Pot: $1.20
Turn: Tc
Hero checks. BU checks.

Pot: $1.20
River: 9d
Hero checks. BU bets $1.20. Hero calls.

BU shows QhTd.

I checked the flop since I noticed that Villain folded pretty frequently after calling preflop raises and I thought that a cbet into a 3 way pot came off a little too strong plus the fact that there aren't really any turn cards that would scare me off. Otherwise, this is a clear cbet situation for me. I didn't check raise for the same reason thinking that if I call, Villain could fire again on later streets. On the turn, I planned to check-raise but that didn't work surprisingly. On the river, I feared a straight so I only check called. I regretted the river check call in hindsight; it was due to poor handreading skills on the spot and I should have check raise shoved or bet myself. On the flop, should I have cbet (despite the high fold frequency), check called (to induce more bets in future streets) or check raised (to get value immediately)?

Checking the flop is not good.

Checking the flop some % of the time for balance and deception is fine but the main line is obviously bet/bet/bet. Once you check there's a strong case to be made for raising the flop and I think this is the best play, we're OK stacking off vs 2x and people will have a lot of trouble folding Qx so that will make up for it. As played check river seems correct, once he bets pot seems pretty close between call and shove.

Checking flop isn’t a tragedy, but it’s probably not the best option. You will want to check call other hands here, like {Q9-QJ, TT-JJ}. By checking AA, you’re weakening your betting range and losing a street of value (though arguably, button will bet most of his hands he will call three streets here). You also lose some information, but that’s not quite as important as the other two points. All that being said, it’s worth noting that checking here gains significant merit if button is overly aggressive in position.

I’m not a fan of check/raising turn here because you almost certainly won’t be bluffing enough to balance out your ranges. Think about it: you would’ve had to have floated the flop or decided to turn a weaker hand into a bluff. Check/raising flop looks okay sometimes, but is also another spot to balance. It’s actually a strong exploitative play here versus button who imo is calling too wide preflop and probably betting a little too thin on the flop.

As far as hand reading goes, I think you’re in a spot I was for a while—seeing monsters under the bed and only really thinking hard when you reach the river. For example, here you say you were afraid of a straight. While this is possible, think about how likely it is that button checks turn behind when he picks up a straight draw. I’ll add also that button’s turn check is pretty bad. A lot of weaker players do this because they think they’re slow playing, but again, here he misses a whole street of value. When he checks turn behind, his most likely holdings are weak pairs that bet to deny equity. You probably should’ve bet river here because of this. If he raises river, you’ll have to do some thinking, but imo it’s the correct play.

It's a safe flop to check with aces but by the same merit it's also a flop that allows you to play a big pot and checking doesn't help you with that.