Hand 1: 7-bet (!) with QJo? It's not a premium hand, m8.
Hand 2: ditto. Draw you line in the sand, but choose a hand less likely to be dominated (even such as 56s)
Hand 3: Raise pre, but try to see a flop. I advocate pushing heads-up only w/ 99 or better (+AK, AQ). However, my heads-up play sucks, so don't listen to me.