lower abd pain/ 4 months post partum

help!

My baby was born in December. I only breastfed for 5 weeks.... still no period and he’s four months old.

additionally, I have lower abdominal pain.

I went to the gyno, she did an exam. I got labs done. Nothing seems out of the ordinary. Anyone have anything similar?? Help!

ps- second pregnancy impossible as I’m in a same sex marriage