Nice name for someone worried about HIV! :-p
Unlikely. The condom probably came off when you pulled out. Did she get it out of her? It could really cause her problems if she didn't remove it!!!
16 year old girls are unlikely to have HIV - does this girl frequently have unprotected sex?
HIV is also very unlikely to be spread through oral sex. Though there is a small possiblity. There's always a chance but with women this age it's very unlikely. If you're worried you can go to a sexual health clinic and have a blood test. It's quick and simple.
At least you're practising safe sex! That's a nice thing to hear from a teenager!