Had partial open nephrectomy 6 months ago and still have swelling and intermittent pain

Some background: 16 years ago I was diagnosed with a 12cm tumor in my kidney. At the time I had no health insurance and not able to get any (due to being a diabetic, pre-existing condition), was depressed from the loss of a child a year before and basically thought well this is it for me, so I decided to do nothing and accept my fate. My urologist at the time told me I would be dead within a year if that was the course I chose. I had no symptoms other than slight blood in the urine and for whatever reason that cleared up. I went for the next 15 years in limbo, always wondering when it was going to happen. No way to live.

Fast forward 15 years I was finally able to get insurance thanks to the ACA and sure enough within a month or two I started having heavy bleeding in my urine so I went to the ER. They ran scans, blood work, etc and the tumor had not grown at all in 15 years. I was referred to a urologist and he told me it should come out but his personal opinion was that it was not cancer due to it not growing or spreading, and the fact that I was still alive. So I had surgery last October and it was removed. Turns out it was cancer, and the pathologist report labeled it as chromophobe renal cell carcinoma.

Anyway, since the surgery I have had swelling that comes and goes along with various pains at the surgery site. It seemed to have been getting better with time but the past few weeks the pain has gotten more persistent. Some could be stress with all that's going on in the world and knowing I have a scan coming up that's been messing with my head. But who knows. The swelling and pain always seems gets worse the more active I am. I mentioned it to the DR about a month after surgery but he said it's normal. Is it though?? It's been a little more than 6 months and its worse than it's been since the surgery (but I have been a little more active). There is like a little knot right under my skin at the incision and that seems to be where the pain is originating. Anyone else experience this at all? It's really messing with my head especially knowing I have a scan coming up next month.