What did I DO?

This morning I met a friend at the gym and went over some basics on how to do back squats, dead lifts and presses. In return, she showed me some should exercises she learned as a water polo player. I used light weights and did very few reps. I was pretty much just demonstrating.

This afternoon I visited my hospice patient for an hour and played my violin for her. Nothing fancy. I was a little uncomfortable turning my head all the way to the left, but it wasn't bad.

And now my neck is killing me! I don't really want to move it. Pain radiating down the sides of my spine, up into my scalp, a little down my right arm. What the heck??