It is normal.
When I was having my first and second daugthers at the very early stage, my lower abdomen was a bit pain, just like you have your menses.
Go to see doctor and take rest.
I am not yet confirm bingo but I already 肚成日陰下陰下痛start from day 19 or 20 today is already day 31 & I always thought that my m will come soon but no. I hope I will bingo soon.