Virgin and there’s a lump at the entrance of vagina?

I don’t know if this is how it’s supposed to feel but I googled it (Yes that was a bad idea) and now I’ve got myself worried about a vaginal prolapse. I’ve been able to stick a tampon in without any discomfort (i’ve only ever used a tampon twice) but it’s something I never noticed as I never insert anything into my vagina. Is this normal? Should I be worried?