This is Dr. David
sperm can not live under the foreskin for more than a few minutes.
men can not contact sperm from public toilets.
your OCD symptoms are making up scenarios which are not realistic.
are you getting medication treatment for your OCD? there are treatments which can help
you may benefit from seeing a psychiatrist regularly and a psychotherapist regularly to talk about these OCD symptoms
cognitive behavioral therapy could help you as well
let me know if you have questions.
no, semen would not survive being transferred from a door handle
it could not get under the foreskin of another man
these are not possible scenarios.