its quite often people will overbet 2 pair, people tend to play sets like AAA and QQQ with smaller bets hoping to entice you.

people will try to defend things like 2p with flush and straight draws out because 2p doesnt hold up much better than top pair, but a lot of people strangely are willing to put all their chips in middle, when its really not an all in and many players can make a lot more money when they stop going all in with 2p.

the big hint here is the pre-flop betting, AA and QQ make it more expensive to go