On hand 1: You didn't have the odds to call, even considering implied odds. Flopped a gut shot which is only 4 outs. The flush doesn't count because it's such a long draw with only 3 on the flop. Good fold and don't worry about the overall outcome. Always play correct poker regardless of the outcomes, you will profit in the end.
Hand 2: I agree with you that it was a weak raise preflop, but on the flop when he raised over you what went through your head? Did you consider a mid pocket pair that might of hit their set? I've made the same mistake many times and have slowed down with the betting at times when I get resistance on possible under sets.
Hand 3: No chips, no chance to make a move post flop. You made the correct play by pushing preflop, but you leave your outcome to chance. That is one of those hands that the lesser hand hits to make the odds even out in the long run.







