I'm 11 weeks pregnant with my second child. I have experienced this pain with both pregnancies. My internet research and doctors have told me it is ligament stretching and is common during pregnancy.
That's completely normal. It's round ligament pain. Happens because the uterus is growing and the ligaments supporting it have to stretch and they can sometimes spasm. Happens to a lot of women when they sneeze, cough, or get up too fast after sitting or laying down. No worries! You can find a lot of info about it online also.
I had the same thing happen when I sneezed in my first trimester. Not sure why it happens but I know it happens to alot of pregnant women. It's very painful but stopped doing it by my second trimester.