Pelvic Pain

Hi, I'm 33 weeks pregnant. I've been having these sharp pains on my pelvic/lower abdomen area. The pain varies on different day different timings of the day and I have been fasting too. The first day it happened after I break my fast and lasted for a few hours. The second day it came with stomachache that made me want to pass motion. The following day I didn't fast and there wasn't any pain. The next day the pain came around 3 pm and lasted almost until night time. It comes and go throughout but when it came it lasted for hours. Should I inform my doctor about this or should I just monitor? I don't think it's braxton hicks since it doesn't go away. I'm not sure if it's contractions because it doesn't seem to be like it. What should I do? Currently having the pain and keep passing gas and feel like wanting to pass motion.