It doesn't seem like it if you don't feel any effects after having unprotected sex, except that bodily fluids of the user can apparently be tested and come up positive for amphetamines, which sort of implies you could be exposed by contact. It might be something you'll have to contact a doctor or even a specialist to find out about for sure.
I don't want to be snoopy, but if you're in a relationship with someone who is regularly taking amphetamines, but are also yourself in a testing regime because of your athletics, it seems like you have a lot to lose by staying in this situation. Can't you persuade him to get treatment for his addiction?