With a bad knee, I don't walk that much. mostly short distances without a crutch. Friday, my knee was worse than usual so I sought medical attention, and had to walk more — so I walked with the crutch, despite having mild "mouse arm" symptoms in that shoulder from overstretching to reach the keyboard.
I woke up Saturday morning with sharp pain in the shoulder. That arm is largely unusable and I am under almost constant pain, and have difficulty sleeping as it starts hurting as soon as I just wiggle a little in bed.
Sought medical attention for that today: No quick fix. Just pain medication and some simple exercises. Should heal in three months unless I do something stupid again. So, now I am crippled in two places with almost constant pain. Great.
Edit: The pain has ceded, but the first week was hell. I just need to exercise that arm a bit. I suppose the "three months" bit is when I get back full strength.