This messed me up for two weeks. Had 2 days off screen use and slept quite a lot. After that had nausea while using computer again, dizziness, vision focusing issues and fatigue. Was able to get to my part time job 5 days later but couldn't last more then an hour without a break. Also coffee started giving me a headache.

The computer use mostly came good around the two week period but still felt a bit dizzy when walking around. Had 5 sessions of HBOT this week which helped immensely and am now basically where I was computer wise 3 weeks ago and possibly better in terms of visual stability and feeling more conscious.

This was definitely more force then a car breaking hard, tyres simply cant stop fast enough to cause concussion unless you bash your head on the window or something.

Comparison would be more like a car crashing into a thick concrete wall at 5km/h with no crumpling and the seatbelt locking instantly and head not moving forward. Table and trolley had no give whatsoever (steel).

Based on calculations I found, when travelling 4.4m/s, stopping in 10cm will produce 10g and stopping in 1cm will produce 100g.

Football Physics: Putting G-Forces In Perspective

Forehead skin is about 1.5mm thick, so at 4.4m/s (running) speed you would produce 666g if your head went straight into a wall or the ground. Walking speed is more like 1.4m/s, which would be 212g - My original injury walking into a wall with forehead.

So if I strapped my head to the shopping trolley we'd be looking at 212g. Though obviously I had some minimal movement in arms, though they were pretty locked as I was leaning forward on them and not expecting the collision.

I'd say stop would be at least 1cm so more like 30g. Not enough to concuss a healthy person but it definitely affected me.

This is the worst hit I've had since my original injuries, and really the only one I think has actually affected me.

In summary, try to avoid crashing into immovable objects, or getting hit very hard while stationary. Everything else is probably anxiety.