Someone yanked/pulled my left hand along with my upper body and now I feel a headache
 

So I was sitting on my bed when someone tried to pull my mobile from my hand as a joke/prank. I resisted, to which they (an adult) put more force and ended up pulling my upper body forward rapidly (similar to a tug of war).

I didn't strike my head on anything nor did I fell down, but this rapid pulling caused some spasm/weird sensations in my shoulders up to my head and now I'm worried that I've suffered a whiplash injury in my brain, or a possible concussion or sub-concussive impact.

My other symptoms include feeling confused and lightheaded.

Can someone tell me what is the approximate g force that my brain might have experienced, or maybe what is the average g force experienced by players of tug of war and whether it is enough for a sub-concussive impact or a whiplash or concussion or any form of brain damage?

Please help!

Thanks in advance.

You're fine! I promise any symptoms you feel are caused by anxiety, not actual damage. I often have moments like what you described, but what I always remind myself is that I've never had a concussion from light movement any time in my life, so why worry about that movement?