I have self-diagnosed and think that I have
bursitis, otherwise known as "handmaid's knee." It's very painful just above the kneecap when I bend my knee, walk, do stairs, and relieves when I rest it. I'm supposed to take ibuprofin and apply ice.
At least when I broke my wrist a few years back, I could say it was from snowboarding. Now my knee is hurt from...doing too much housework?