Could I go into labor soon?

I’m 39 weeks pregnant and I had a normal day, didn’t do much. I got home from a friends house and my bottom half is extremely sore (I wasn’t walking or anything) I keep having period like pain but they aren’t consistent. My inner thighs are really sore also, and I’m having a lot of pressure on my butt. When I try to walk my legs feel weak and shaky. I’m a first time mom so I was wondering could this possibly be labor coming soon or no? Also, my baby is still active so I don’t know if that matters.