Am I cumming?

Clareth
I hope this post makes sense lol idk exactly how to describe it but Hey girls!! so my name is Brenda & I'm 20 yrs old and been sexually active with my boyfriend for a while now. 
Idk if it's just me or if there's more girls out there with the same question in their mind.... anyways, the sex with my bf is just mind blowing I don't even have to fake orgasms. But the thing is, he's always asking me if I came because nothing comes out of my vagina so he doesn't believe me when I say I did. like for example there's girls who squirt or 
" cream " (looks like a white discharge or in other words ' female cum' if I'm not wrong. ) ... 
so when I'm "cumming" I can feel that something wants to come out (idk if that's when actual 'cum' wants to come out) but if it is, my vagina isn't letting it come out & I say that because I can feel for some reason my vagina muscles contract and don't let anything out... is that normal? Do all girls let out actual cum or squirt out their vaginas when they're orgasming or is it just me that I don't ?