Yes, most definitely loosen up. If the blinds are high enough, I would go all in with any pocket pair above 5's preflop if I'm small blind. If they call, it is most likely that they have Ax, Kx, or Qx, and you have at least a 5% advantage, 40% if one of their cards is lower than your pair. If they fold, you take his blinds. Heads up is more about luck, because the finishing hand will usually involve a lot of luck.