there is no reason to worry about having an orgasm, or cumming, just yet.
my mum was on her second husband and 4th child before she had her first orgasm, you just need to know your body, the better you know your body, and your partners body, the better sex becomes.
my older sister had an orgasm the 3rd time she had sex. it took me until my 3rd partner to finally figure out my body, now i have to put a towel down before i decide to have sex, or i am forever changing the sheets.
i also experimented with another man while with my 3rd partner, the 4th man i had sex with, was no where near as good as it was with my partner.
i knew how to work my body, but because i didn't know how his body worked, it wasn't good sex at all. it was awkward and i just sat there thinking about my partner, wondering why i decided to do this.
everyone is different, i have a male friend who can only orgasm when he is on top in the missonary position, and a female friend who can only orgasm when she is being done doggy style.
the key to a good sex life is communication.
if your having sex with them, than you should be able to ask them what they like, and tell them what you like.
if your unable to talk openly with the person you have having sex with, than you have to reconsider where your life is taking you.
sex is great, the purpose of sex is to create new life (that and it feels great) if you having sex with someone, than you should always consider the possibility of creating a child with them,
if you have not considered that, than you should reconsider having sex with them.
sex has many powerful emotions attached to it, so pick your partners carefully, that decision should not be taken lightly.
just be open, happy, healthy and enjoy life.
it's not the end of the world if you don't orgasm!
life is short just enjoy it!!!!