dude, i am in the same boat...dont worry about it. most women i know dont like to swallow and most men they have been with cum too soon it ruins the night, so when they find they can suck me for an hour and i dont cum in 2seconds and am still hard they seem to love it.
i have cum close (mind the pun) when we were in a 69pos,me on top. the angle felt so good, and if it wasnt for her gag reflex i would have blown an almighty load down her throat...oh well. Dude its cool, go with it!!