"Challenging yourself" can suck it

I'm trying to push myself a little more in yoga and try things that terrify me force me to risk and grow. So last week's attempt to push myself over from a back bend ended tragically with me getting my legs straight up and then I collapsed before completing this back-walk-over-type move. Result: giant gnarly bruise on my left shoulder that is finally turning yellow and fading. I'm telling horrified observers that someone "Chris Browned" me. It sounds better than the truth: that I am old and dumb.