This is none of my business, but how you know that he was the one to give you this "parasite"..? Did he tell you he had a parasite or were you just assuming he gave it to you because he's "gay"? What does that have to do with anything? I mean, I'm straight and this is still feels offensive to me... Anyways, I'm not an expert by any means, but I am not aware of a parasite large enough that could cause you to instantaneously feel as if you've been infected. Many parasites are actually quite tiny and unnoticeable. I could be wrong though...