Belly itchy in spot that hurts at night

I’ve been having a spot to the left of my belly button that has been hurting in the evenings for the past few days. Yesterday it was hurting BAD and I had to stop doing laundry and sit down - it stops hurting when I sit down. I messaged my OB and he said that he’s not exactly sure what could be causing this and it might just be the muscles stretching. He didn’t ask me to come in. But, I was doing the dishes just now and sat down, and the same spot that I get the pains was super itchy.

Does ANYBODY have any idea what this could be? I’m 29 weeks.