However if neither of those happen I play aggressively and end up getting bitten by the trips or 2 pair. or if I have 2 pair I get bitten by the trips or completed straights on the river.

My main question I suppose is should I always give the player credit for his hand when he raises and I don't have any reads?
The thing I find is that generally people at this level don't know when they are beat (including me sometimes) and so they will call a large re-raise with TPTK or draws when you obviously have trips/straight/flush.
Looks like you already know the answer.

On the part about having no reads on a player - you should respect the bet for what it is until you know otherwise.