Can't orgasm because of antidepressants?

Hi I'm a little embarrassed about this one. I'm a 16 year old girl and Virgin, my hormones are driving high- as they do(!) my problem is I'm on 150g of sertraline the anti depressants, so I can't find relief basically. When I try to "relive" the problem shall we say I don't orgasm or get any relief. I rub my clit until I get a tingle feeling but then it stops suddenly. I don't know what to do or if I should tell my doc incase it's a side effect, but I've never been able to get relief. I get the normal stuff like getting, erm lubricated but that's pretty much it. I don't want to have sex until I'm married- I know it's outdated but that's what I believe. Any help would be really appreciated as its getting me quite depressed. Thank you x