Fall from grace

On Wednesday I got thrown off and I don't remember it. I went out with Angel, she was doing well on the road, and I decided to go in the field where we have historically had troubles, but lately I have had lessons there and she has done pretty well. I mean, I have not even fallen off at all! So we went to the front end of the field, presumably less exciting than the back end. We did little circles. She did great. Then, I remember going up in the air, not seeing much. Mind you, I was still on my horse, but she was rearing. When she came back down, and I was still on, I shouted angrily at her but did a few more circles so she didn't get the idea that rearing would get us out of the field.
And after that, I remember being home, wandering around talking to my son, and the ambulance coming, and chatting with the ambulance people, and then hours and hours in the emergency room. They tested my memory by asking the date, and I was great at the month and day, but could not think of the year for the life of me. I spent a long time puzzling on that, and was pretty smug when I got the answer. They kept surprising me by telling me things about my horse that I couldn't imagine how they had discovered, only to be reminded that I had told them myself. The short version of this story is that I had a concussion, obviously. I had no headache.
I cannot remember the fall, I cannot remember how I got home, I cannot remember untacking the ungrateful Angel, or calling the ambulance. Apparently I chatted with an ex-coworker for a while, before telling him I had to hang up to go check on the ambulance, because "those guys ought to be here by now".
The only lasting result is a great pain in my side, and a great suspicion of myself. I started making apple sauce without cutting up the apples first. "Brain damage", I hissed. I headed in the wrong direction to get water in the barn. "Brain damage, see?"
And I am left with a jaundiced view of Angel and less confidence in my own judgment.