Absolutely not! This is normal and I respect you for that. Just make sure you use safety methods for std and pregnancy. Be gentle and let her guide you to what she likes. This will make it more pleasant for you both.
She may be more experienced that you, so allow her lead you.
You may not be the first one to do her, but believe me, this is a hell of a better deal that being the first guy. I would rather be with one that has had another before me. At my age, there're not to many virgins left out there and if there were, I wouldn't want to have sex w/ them.
Good luck, be gentle and be safe! :)