Sorry to learn of your crash and I hope you are making a quick and full recovery.
Your symptoms appear to be similar to what I experienced a few years ago: although I didn't crash our tandem, I had temporary memory loss and kept asking my wife the same questions. I suddenly couldn't remember where we had come from or where we were going, and it took about an hour of rest before things began to clarify. Dr, Google told me it was a Transient Global Amnesia (TGA), as it had all the symptoms, but my cardiologist insists it was a TIA, without any of the symptoms! I've been fine since.