they told me they were on their way back from the loo and the aircraft seemed to pitch nose up but not so that they lost their footing and flew off the floor but when it came down it was quite severe and this person said their legs felt like they were crumpling under them
That's completely the wrong way around.
If you pitch up, you crumple to the floor as a walking pax.
When you pitch down, you float off the floor.
Has your friend got it right - did you read your own post?