me and my girlfriend want to have sex

Me too but were fifteen, both virgin.

ask your selves these questions:

can either of us get condoms?
(if you feel nervous going to the store and getting them you shouldn't be having sex)
can we be parents?
(your 14 i doubt it)
have you had a conversation face to face about having sex, not just one person talking?
why do i want to?
how do we feel about each other?

if any of those answers were responsible, honest and positive, i say go ahead :]