Abdominal swelling 12 wks post-op

I am 12 weeks post-op for a TAH and BSO, combined with a small hernia repair. My incision runs from 3 inches above my belly button all the way to my pubic bone. I was doing fairly well and went back to work after 8 weeks.
I now have swelling that extends the length of the incision and runs 3 inches of each side, to a 6 inch total width. This swelling is hard and putting a lot of pressure on stomach and intestines. At times I am nauseated from the pressure and I am having difficulty any time I stand up for more than a couple of minutes. Walking any distance is out of the question.
Any ideas what this could be? Doctor has no idea what it is...doesn't seem like fluid. Could this be the way adhesions or excessive scar tissue show up? Or could it be a hematoma?

Can you ask for another opinion from another doctor? We have a similar incision, about a foot long in total. Mine was done 6 days before yours. I did not have a hernia, but I did additionally have appendix out. The kind of swelling you are describing I am not or have not experienced. Mine has been what I think is typical lop-sided swelly belly, on and off, day to day. Yours sounds like incision specific, something going on with that cut. I can feel some slight internal swelling, or gas, but not a hard strip like you describe. My belly is sort of all the same consistency (ummm, not toned at all) and the line of scar tissue feels like it should, I suppose, hard only where the cut line is. Some numbness mixed in with sensitivity, but nothing too unusual. So, I guess what I am thinking is that yours sounds a little out of whack! I guess it wouldn't be so frustrating if your doctor was able to tell you this was part of the normal healing process. I think you should keep mentioning it to your doc, or ask to see somebody else if possible. Good Luck to you!