Long story short:
I was using a massage gun on my right leg using my left hand to hold the gun. I was lying down and after about 15 minutes, I tried getting up and my left shoulder hurt pretty badly after seemingly having done nothing.
After two days, the pain is still there.
I went to my doctor this morning and he is 95% confident it’s biceps tendinitis caused by holding the massage gun…
Has anyone experienced this? It’s slightly ironic.