Did you report to a doctor?
TIA is so transient (hence the name, lol) that they can't even be confirmed by doctors, so it's hard to say.
My first TIA was one week before my stroke. I had just finished my first and only session of EMDR for trauma recovery. The process was very overwhelming for me and caused near catatonia. As I was leaving I lost all balance and the ability to speak. I slumped and fell much like you did, but on flat ground. I had no control of my muscles or movement. It lasted about a minute or 90 seconds max but seemed much longer. I assumed it was from the trauma and carried on with my day.
My stroke was a week later and caused by a blood clot to my cerebellum. This was a much more serious event and I needed a year of rehab to recover balance.
Since the stroke I've had a few of those lesser experiences again. My neurologist said that they are TIA and that the first event was likely a "warning" TIA.
Back to the original question!
What was your most embarrassing injury, and where did it occur?
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I never give you my number, I only give you my situation.
Beatles