Tampon

Hi I'm 17 and I've recently had an interest in trying tampons out. So I attempted putting a tampon in but can't get it fully in, only half way until I start to feel a dull sharp pain (not sure that's normal) but I'm not sure what I'm doing wrong I don't think I'm doing it at the right angle, but I've been able to get my fingers all the way in. So I know I can get it up there but I'm just struggling to do so. Any tips or advice that would be very helpful.

Thanks x