I woke up just a few minutes ago and my lower stomach feels like it's on fire! It hurts to move even…

I woke up just a few minutes ago and my lower stomach feels like it's on fire! It hurts to move even a little! It's all the around my stomach and my lower back. It's even hurting my vagina! A little (TMI here) my anus is doing the same thing!! It hurts to sit or move! I'm worried because I've never had this! I'm 20 weeks pregnant. I've asked my mom and she said it could be ligaments stretching, but I just want to make sure it's nothing I should be worried about!!