How to stop being tight

So to start off I can’t tell if I’m just doing it wrong but I can’t put a tampon in bc it hurts rlly bad but I can put 1 finger in which is weird but once I try to put a second finger in the pain is excruciating and it feels like I’m hitting a wall on that the opening is too small and I want to have sex or get fingered but idk how to get “looser” or have it be pain free and feel good?btw I’m 14 what should I do??