Baby dropping while walking?

Lately I've noticed that while I'm walking, my daughter will drop super low to the point it feels like she's going to just fall out. I'm almost 31 weeks. It's uncomfortable and sometimes painful when it happens, and I will lift my belly up in hopes she'll move up a little, but she stays there for quite a while. Does this mean she might be coming soon? I see my OB tomorrow morning, so I'll be telling him about it. Maybe I'm just being paranoid 😐😔