Wrong Cup??

The cup i’m trying to use is a ‘Kind’ cup but it has quite a short stem and when i try to get it out i always end up pinching and hurting myself with my nails. So I’m scared to push it in too far incase the stem is too short and i can’t get it out. I’m only 14 so maybe i shouldn’t be using one?? But i just spent £20 on this and I’m worried i got the wrong one, any advice for me??