No one can say for certain what is causing your pain. Many people have similar pains and offer advise based on what happened with them. If you are worried and its an abnormal pain youve never felt before, call your doctor.
Maybe its your Sciatica nerve acting up mines is n it can b horrible feeling
I have a sharp pain sometimes in my pelvic area, but I noticed it was after the baby moves like crazy. so that's what I think it is, for me anyways. I'm 31 weeks