If he calls you, save the message. If he writes to you, save the message. if he requests anything of you online, take a screenshot of this request or any string of conversation.

Make sure to also keep the messages in which you've asked him to leave you alone.

If he continues, take everything to the police department and file a report. They will pay him a visit. Stalking is against the law.

((((hugs))))

ps, just because he is a doctor doesn't make him a good person.