Welcome to the board.

On the 1st hand, I would have bet like $.50 or $1.00 after the flop just because it seemed like everyone had a weak hand from all of the checking going on. The raise you made was too high, but you did have to worry about a flush draw on spades. I would have raised it a $1 or $2 and as long as a spade doesn't hit, bet like $5 or so on the river.

The second hand you played well in my opinion. No sense in betting like a maniac just in case that full house hit. I've seen plenty of people lose lots of money on a flush or straight to a possible full house showing. You could have tried another $3 raise if you were confident in your hand (like 75% sure you had the best hand).