Help me please

I am 18 weeks pregnant. I am pregnant with my second baby. And my first baby was born at 24 weeks. This pregnancy I have gotten a cerclage to help stop preterm birth. However last night I start getting these cranky feelings in my stomach. Kind of like a really bad stomach ache. But I’m not sure if they are contractions. I’m just so nervous I don’t know if I should go to the hospital or not. I can’t remember what contractions are like it’s been 4 years. What would you do? I have an appointment with the dr tomorrow morning. Should I wait until tomorrow to talk to him about it?