I think I'm having a miscarriage

I have 2 kids. One is 2 but very tall & looks like he could easily be 4 so he's big to say the least. The second is 7months almost 8 months. Last week we went to visit family a few hours away I had abdominal pains & nausea vomiting. I thght maybe it was just some bad food or something. Since then & especially Yesterday & today I'm still having abdominal pain & cramps. I have an appt first thing in the morning but I'm scare I miscarried. I'm 10 weeks I almost lost my 2nd child at 13 weeks. I have no bleeding like I did with my second but I know that doesn't always mean anything bc ur body may not always recognize it right away. Am I having a miscarriage? Have I just been doing too much with my older boy maybe so it's causing some pain? Is it bc this pregnancy is so close to my last baby's birth & I just need to take it easy or am having more pain bc I wasn't quite ready? My mind is racing. I'm scared & to think I've lost my baby is killing me inside right now. Anyone have anything similar happen & everything was fine? Or did u miscarry? My husband is in tears crying trying to keep it together till our scan tom morning. I just need some support good or bad so I can prepare for what might happen.