How severe are your cramps?

I've had two previous wart miscarriages at 5.5 weeks (I was in grad school and stressed to the max). But when I lost them I had horrible heavy cramps as my first warning sign. I'm 4w3d and SO NERVOUS every time I have a cramp. This pregnancy feels different Bc I can actually see my uterus wriggling at my desk as it expands and I tested positive 8 days before my missed period. However the cramps are terrifying. I woke up at 4am to severe cramps. They were low and almost felt like giant bubbles of gas but super painful. I counted about four deep pains in my uterus and then it stopped. It's so hard to not overthink and immediately panic I'm having another mc! I have a theory this is a part of the "bubble stage" where bubbles of gas are being pushed out of the cervix. How is everyone else's cramps?