Ok never had twins before but the last week off and on and today hardcore there has been pain behind…

Ok never had twins before but the last week off and on and today hardcore there has been pain behind my belly button and above nd on the left side. It's so bad. I also when it happens kinda feels like a grinding and I end up pooing and now puking bile any clue what's wrong primary dr nurse seemed to say gall bladder which I don't have and I still don't have appt with high risk dr office yet at almost 12 weeks