Lower belly pitting edema

So I’ve been noticing a pooch forming in my lower abdomen over the last week or so. At first I thought it was just a weird belly fat accumulation. I also noticed I could feel deep, tender stretch marks over it that showed up out of nowhere. I assumed I was scratching my belly in my sleep since I have PUPS (absolutely miserable 😩), but the area is so tender and sore. I started to realize that my underwear or shorts waistband was creating lines in my stomach even when they aren’t tight, so I checked by pressing with my fingers and they are leaving indentations, as well. I’m 35-5 with didi twins. I see the doc in 3 days and will bring it up then, but was wondering if anyone else has had this problem. I have had little to no swelling anywhere else this whole pregnancy and my bp runs low naturally. It’s just so damn weird!

Sorry for the long post 😊