Could Bump At The Vaginal Opening Be Due To Tampons?

Hi, I have the bump in my vigina and I've had it for some while now..it comes and goes....but right now it won't go away,it has a bumpy rigid touch to it...and I'm kinda concered about it. Its in my vigina enterance. I mean I can feel it when I stick my finger in there to see if it when down. But lately it hasn't. Could it be because of tampons? Or being sexually active.? I just recently moved to the U.S and I can't really afford to pay doctor bills. I'm really concider.I need help! :( I'm scared about the out come. Just need an answear. Please help!!!!!!!