Russian Rocket? Sorry, it just struck me
funny considering the topic.
Anyway, Eiri is right, you are probably
having anxiety feelings. Just relax and
make sure, as she said, to be in a place
that is secure and you won't be
interrupted. Take deep breaths so that you
don't get too excited and do the deed.
There is no reason to be nervous because
it's your body and you need to start
knowing how it works. And, of course,
there is nothing wrong with masturbation,
so stay loose and have fun.