PLEASE HELP IM FREAKING OUT! Nose peircing!!?

Okay so i'm on holiday in Greece and was really eager to get my nose done as i was inside this peircing place on impulse. Without looking into it I didn't realise that there was much difference in guns or needles, too me honest i'm just a 15 year old girl and I don't know sweet f a about it. So when they pulled out a peircing gun I didn't think anything of it, so they did it ect ect, hours later i see it is sticking out, freaking out i run to the mirror its half way sticking out i dont know whats going on in the inside i cant see any metal and its very swollen, i cleaned it and tryed to push it in but the pain was unbearable, PLEASE help me or atleast explain to me whats going on because i can't go back to the piercers untill tommorow morning since everythings closed now. THANKS XOX