Hi, no, you don't have anything to worry about, especially since it was your own toilet.
I also have very bad anxiety, but please rest assured you really have nothing to worry about at all in this situation.
This is something that mainly happens to people when they go to the toilet in normal setting. Toilet water can splash your but and it could be cut. There is tons of water that would kill / dilute anything that would be there if anything at all. Nothing to worry about. Find someone to talk to about your anxiety because it sounds like that is something you are having a great deal of. Ask your doc for a number to call.
I agree totally with FurballsMom. The only thing you are going to get from a toilet is the heebie jeebies. I mean, I wouldn't let a kid play in a dirty toilet, but you really have nothing to worry about here.
I sometimes get backsplash myself. Overall there is nothing to be overly concerned about as long as everyone is in good health. People with a healthy immune system usually will not get sick over this kind of accidental exposure.