Maybe you are worried about getting her pregnant
or something such as that. May you are religious and you think that you should be married in church before doing this to your virgin girlfriend. My advise is that you just wait six more months, date her and do not try to have sex until your ideas mature more. In these six months, mentally figure out what is going on in your head. Maybe you are the type of person that needs to be married before doing this act that bonds you to her for ever.