Partly anxiety and part curiosity on the science. For example, I remember reading of your example of a bowling ball dropped from two feet. I have trouble mentally gauging analogous situations to other more common examples like two people's heads bumping together. My spouse's head obviously does not weigh anywhere near a bowling ball but her body weight is 150 lbs and she traveled the same distance as a bowling ball but in a different direction and perhaps speed. Basketball and soccer players seem to get concussions jumping a few feet and clashing heads. Not sure if my situation could be in the same category.

We have some socially distant outdoor group sports that have resumed; trying to gauge whether to rest up and take it easy or continue as usual. I know I'm not talking to doctors and wouldn't suggest that. But I enjoy hearing of people's experiences and thoughts nonetheless.

That's interesting regarding TMJ cushioning a blow before damage is done to the brain, by the way, and something I didn't know. Boxers seem to target the chin for "knock outs" and are often successful. Pros seem to take a lot of jabs to the chin without being knock out and perhaps not concussed, and again I have a tough time making analogous examples of force. A headbutt to the chin is something I haven't really observed, although I know headbutting in general seems to be a potentially dangerous move in pro fighting.