this is so unusual I kind of love it I dont want to scare you but there is a chance it'll be flagged dont worry about it though because this doesn't mean it'll be disqualified usually they flag papers that use inappropriate/concerning language like if you wrote 'f whoever is marking this'. However if images are offensive/a safe guarding issue they have to report it again this doesn't mean ur cooked. Maybe send ur exam officer an email I would basically say you had time left in an exam and started to get anxious so you doodled on parts of the paper and the exam ended before you could get rid of them/before you realised this could be an issue and you wanted to make sure that this won't mean you'll be disqualified (they might contact the exam board on ur behalf to explain u didn't know if they are quite involved but maybe not), I genuinely think youll be fine maybe pursue art over physics in the future😭.
I've had a little look on another forum and the most people tend to get for writing/drawing something bad is a safeguarding concern