[Rococo]

I think that the 7K kid played hands 2, 3 and 5 very well, and knew almost exactly what you held in each hand.

Calling the turn raise is probably better in Hand 2, because of the possibility that Villain will make top 2 if an A or some such card hits on the river. It also increases the odds that he will "value bet" a 3 on the river. If he has a boat, you are get plenty of money in no matter how you play it.

Those who play a lot shorthanded would recognize your flop raise in Hand 3 as weakness, not strength. It fairly well screams, "I have a crappy ace and I really want to be able to check behind on the turn." He recognized that and rightly put you to the test. Calling (which is scarier to him than a raise) is by far the proper play here. Plus, he may try and value bet the river with a middle pair if the turn goes check-check, which it often will.

In Hand 5, the previous action (i.e. Hand 3) makes it more likely that Villain has a hand here, not less likely. I have absolutely no idea why you concluded that Villain didn't have a 4 based on his preflop play. With position, stacks this deep, and your prior history with Villain, I believe that Villain could literally have any two cards here.