Sounds like things are just fine to me. Flaccid size means nothing really. What matters most is that it works and you know that it works. Just a tip though, the first time isn't always the best. Your penis is used to your masturbation habit...speed, grip, technique etc....try as we might we simply cannot create a vagina to masturbate with. Your penis might have some "issues" getting accustomed to the real thing. Also, nerves, performance anxiety and all that may get in the way a bit. So, don't put too much pressure on yourself...this is a process that takes some practice. Take your time, have fun and the two of you should work together on making this work, and it WILL! I'd suggest that rather than going all out for sex on the first time....play around, do some mutual masturbation with each other and just get used to being sexual together...then add intercourse, and no it doesn't have to be on the first time attempt. Just have some fun and be creative. That'll help with the nervousness and some of your fears about size and things working right.