Is it normal that i can't stand used tissues?

Used tissues lying around bug the hell out of me. I can't stand picking up tissues after people when they leave them on counters, tables, or even (my boyfriend does this) stuffing them inside the toilet paper roll in the bathroom for a later use! Just throw the damn things away, I don't want your mucous and germs. It's not like I have many pet peeves when it comes to things like this. I'm pretty much the outdoorsy/dirt under the fingernails type; riding horses, mucking stalls, sailing, and deep sea fishing is never any question or issue... but a little tiny tissue can get the better of me? It makes me want to gag just thinking about it... which is really odd.