Strange belly pain, pressure, and tightening

Anna-Grace • Married mama to George ❤️👦🏻
FTM, 32 weeks. Today I took a walk in the air conditioned mall. I used to walk every day but stopped in June because of the heat. Anyway, I started feeling sharp pains in my belly, sort of around my belly button. I would say maybe 4 inch diameter around belly button. I normally feel hard spots in that same place and baby likes to kick there often. The pains sort of felt like gas pain or a stitch you get when you run sometimes...that's the best way to describe it. I felt the spots and they felt much tighter than usual, most of my belly did actually, but the pain was located to this circle area around my belly button. My actual belly button is not sore and there's not really pain there. The pain felt like my son was going to burst through the center of my belly, there was so much pressure. I did notice mild lower absominal cramping too (kind of like period cramps) but that was a few seconds later. Once I stopped walking and set down it dissipated slightly and after drinking some water and laying down on my side, I'm much better, but that area still doesn't feel great. The tightness seems to be gone as does the sharp pain. Im just sort of left with mild dull discomfort there now. I don't want to call labor and delivery because this doesn't appear to be an emergency but it is wigging me out all the same because I can't figure out what it might be. After googling it, sounds like it could be either an umbilical hernia, pain from my ab muscles getting ripped apart by growing baby (yay...and the midwife does think I have diastasis recti since my belly does that pyramid thing when I lower myself onto my back), or Braxton hicks. Has anyone else experienced something like this before and have any ideas what it might be??? Obviously I'm hoping it's just Braxton hicks but I don't usually see them described as sharp, side stich type pain like what I had. I did try laying down to see if the pain moved thinking maybe it was gas (although it seemed awfully high up to be gas pains) but nothing happened so I don't think it's gas.