Braxton Hicks or Crazy?

I feel kinda dumb for asking this. I'm 30 weeks pregnant, and my boy has been just bouncing off the walls down there! ❤ A few minutes ago I went from sitting on the floor to standing up (with a lot of discomfort and struggle, mind you!) and as I'm walking out of the room I get this cramp-like tightness below my belly button/lower pelvic area. It lasts over 40 seconds until I sit, and even now the "muscle" or whatever feels a little bit tight. As I've understood, braxton hicks are typically higher up and cause your whole belly to tighten, right? Or no? Is what I have BH or just a cramp? It's probably not important but it was so weird I thought I'd ask.