[FairyPoppins]

Urine is sterile when it leaves the body.

It's only when it's been exposed to air for a while that bacteria develops and, if it's been sitting in a catheter bag, that's unlikely.

So unless

a) He had blood or a disease that can appear in urine (unlikely) AND
b) The pee went into one of your mucous membranes (which it sounds like it didn't)

... you really shouldn't worry.

Sorry about the poo situation though. That would have really grossed me out.