BH Contractions?

Not sure exactly what BH contractions feel like. With my miscarriage a few years ago I experienced real contractions. I've heard varying things about BH, someone told me they feel like regular contractions, and then I read that they're different. It's not really pain I'm feeling, more like discomfort in the bottom of my stomach, when I first felt it a few days ago I also felt lower back pain and I felt like I needed to use the bathroom and I did, but tonight I felt like I needed to and couldn't. It's the discomfort in my stomach, my lower back always starts to hurt as soon as my stomach starts and tonight I felt like I needed to go to the bathroom as well as vomit. Also discomfort in my bottom. I'm not worried so much as just curious. I also am not sure I noticed the squeezing sensation I've heard about, I'll try to pay attention to that next time.

It's like a tightening sensation in your belly. For me, it wasn't painful, just uncomfortable.

Im 21 weeks, and I feel like I have had that off and on for about a month now.... aspecially when I lay on my back. I feel my lower tummy start to feel pressure, and then it gets super hard for a couple seconds. Sometimes I wonder if its the baby balling up. But I dont think it is. Noticed too, it seems to happen more often if my bladder is full.