36 weeks - cramping pelvic pressure and feeling of gas

Today I woke up with some cramping in the morning (almost period like cramping). I am not bleeding or anything. However throughout the day I felt this discomfort. Now as I am laying down to try and sleep I have noticed that it now feels like a pressure in my uterus. It’s almost like there feels like a big air bubble/gas bubble in my uterus that my baby is pushing down on causing the cramping discomfort. It’s making it impossible to sleep. When I talked to my OB about it today he said that the cramping at this point in my pregnancy is normal (I’m 36 weeks) and it could potentially be early contractions. I just wondered if anyone else has had the sensation of that uncomfortable almost gassy feeling but instead of located in your bowels it feels like it’s in your uterus?