Probably not.. because they hate it when people scream in their face anyway. I would probably just start talking to them and get to know them.

Most probably not, because I am socially anxious no matter who I hang around with. Besides, I wouldn't want to scare them off and/or bother them.

Well I would try not to, but I don't know if I could contain myself ;).I wouldn't scream coz that's creepy, I might cry tears of joy though (but I can't help that)