It’s simple overstimulation and all cats do it. You can’t give them a shitload of stimuli or they’ll start losing their mind - biting, scratching, flailing. Then they’ll usually move away to chill out so they don’t get stimulated further. Imagine being ticklish and getting tickled by some a-hole for way longer than it’s funny. Yours was just trusting enough to sit in your lap after. The head pressing is normal too, cats feel safer when they are held tightly / pushing on something. Google “squish that cat” - it’s a 7 minute video on how to handle a cat. My cat does the head push when he had a bad day too.
Well, she got RRRRRrrr and biting (but not running away) in overstimuly mode after the “fix”. Look, she was inbred and clearly autistic, different but way smarter than other cats (was a farm and she’s ca. our 30. cat; i do know how they behave usually). My guess is more that she got trusty enough to me/us during that training to feel safe enough to not panic.
