Hey man, just relax its cool. There is no reason to get worked up about sex. First to answer your question about an std....No you do not have an std. If you are a virgin, there is no possible way for you to have an std. Sexually transmitted diseases may be transferred orally, but, it is not nearly as likely.
If the girl you are planning to have sex with is a virgin also, then you should feel somewhat better about it also. She will be equally nervous as you. Just try to relax, and always make sure that shes 'okay'.
Alot of girls do like men who shave their pubes. However, there are also alot of women who could care less. The way I shave them is by using an electric razor. I never shave it off completely with a razor and shaving creame. I get it to what is somewhat like a "5 o'clock shadow" ...Which would be...Very small hairs, heh...Anyways...Do what you want. Pubes or no pubes, a dick = a dick.