The toilet is clean comment is absolutely appropriate in talking about OCD. The fact that they found it so funny shows a very low maturity level. The fact that a classmate walked over and shared it with them shows zero respect. Is there any chance you would be up to talking to that person and saying, "listen, I'm still trying to feel comfortable in this class and when you shared my answer with them, it really made me uncomfortable,"? I know it will be hard, but people like that have no idea it bothers anyone until they are told about it.

Don't stress over the second issue. If you were supposed to get her email address anyway, she would have no way of knowing you didn't get it and had to get it off another email.

Relax, dear friend. Let your mind take you someplace calm and quiet. You have done nothing wrong, nothing to stress about.