Contractions?

I had a weird feeling in my lower abdomen last night (assuming it was my uterus). It didn't hurt, just felt aware of almost a tension going on and off for a bit. Stopped after an hour and a half. Of course I was googling and whatnot and I read that women can start getting Braxton hicks contractions as early as 16 weeks!

I'm only just about 18 weeks, but thought it was WILD to learn this. Any ladies out here been pregnant before that have experience with this?