Hi. From what I can tell, sometimes its natural to have such thoughts or dreams. Its part of your mind exploring who you are, and are not. Also, sometimes, I've read that, your mind can actively pursue thoughts that may make you uncomfortable.

As for advice, I guess the best advice I can try to give, as someone that overthinks, is not to let yourself obsess on it. Or just plain talk about it.(as you are doing now)

Sorry if that doesn't help much, but thought I'd at least try and give some info if nothing else.