it may be just too intense for her. if you're focusing alot on direct clit stimulation, dont do that quite as much. focus on the areas right around her clit and maybe she'll be more comfortable. And yes, you can still get an orgasm from just around the clit. hope this helps ya. good luck.

dont worry about that right now
like the other guys said dont try to make her keep going. if she says it feels too intense...back off a little and slow down.
some girls who have never had an orgasm are sometimes afraid of the feelings. im not quite sure why tho?
maybe you could ask her. i mean are you sure that she's enjoying herself? communicate ask her why she wants you to stop. have you been able to give her orgasms any other way or has she never had one?

sometimes tho it does get to be too much and too much stimulation on the clit starts to hurt more than it feels good. maybe that is her problem.

just dont put too much pressure on her to have an orgasm and just enjoy the moment. especially if/when you guys have sex she'll feel like she HAS to have an orgasm every time to make you feel happy and sometimes its just not that easy.
some days i can orgasm like 2 mins after penetration. other days it takes like 20-30 or till my b/f gets tired lol.
all im saying it just go w/ the flow right now and not focus too much on the orgasm. just make sure she's comfortable and enjoying herself.

any stimulation can be enjoying even if you dont have an orgasm. those are always just the cherry on top

.. yea , mostly what mike said , but you should take it slow . keep doing it , untill she gets used to it ,, and then she will be more comfortable with the whole situation ,, you cant just rush it , wait for her to atleast get used to it before you go for the goal .

It could just be.. to intense. Especially if she hasn't experienced it much before... just take it slow, if she wants you to back off for a bit then don't ignore her and keep going, thats only going to make things worse.