I injured my knee a few years ago and I'm starting to have alot of pain in it again.?

Im in the military and suffered a knee injury a few years ago while playing racket ball. Long story short - I fractured my patella and tore my meniscus when my opponent slammed into my knee. I was able to avoid surgery though physical therapy but my knee has never been the same. I have been running more lately(which is not an option) and my knee has been hurting more and more. After running there is some swelling under the knee cap(not behind). What can I do to help this? The obvious answer is stop running or go back to the doctor. I was hoping for some sort of brace that will assist and allow me to continue running. Any advice would be appreciated.