Hi,
Here is just one link for some more information:
http://www.onlinedatingmagazine.com/...pubiclice.html
No, just sitting on a toilet will not infect you; normally.
I do agree with the other post about seeing a doctor. Please see one, get treatment, before anything gets worse. It's much better for your own "peace of mind" to know, if anything is wrong, and what to do about it.
I do wish you the best.