Braxton hicks are obviously normal, but pay attention to when the contractions come. Are you having multiple during an hour? Then I'd really call your doctor. I'm on my first pregnancy so I don't know if it's related to the fact that this is your second, but the doctors are there for you to use :) Give them a call when you're feeling unsure!
This is my first pregnancy, so I don't really know, but I would at least call the dr. If they seemed concerned, they can easily have you come in or move up your appointment. Better safe than sorry!