That happens to me too. With me it turn out to be a cyst on my ovary and that's where the pain was coming from. You should ask your doctor about checking your ovaries when you have your next ultrasound.
I have this happen a lot now. It will bend me in half if I'm standing lol.
Its just almost scary how strong they get sometimes, the one this morning was so uncomfortable and I was almost sore the rest of the day
I get it two amd it hurts :(
I have sneezed and wet my pants that's why I wear panty liners all the time.
Just wait till you sneeze and pee yourself