I am 31 weeks and am having my second baby. I am having the same thing I was wondering what that was. Thank you for the information.
It could be what is known as crotch lightning. (Yeah it's a thing) best way to explain this is it feels like a sharp pain, fast, kinda like a needle is poking. If this is what it feels like feel free to Google: -)
I've had this since 34 weeks. Catches you off guard then it's gone just like that. I was thinking what in the world?? Lol
It's probably the baby kicking and putting pressure on your cervix.