Is It Normal To Have A Painful Lump On The Bikini Line Area During Period?

hi i've recently discovered i have a lump on my bikini line it's kind of wear you get that "triangle" tan line but it's on the left side of the "triangle". i'm on my period and so i don't know if that has anything to do with it but theres not one on the other side and it is VERY painful. it's not an ingrown hair because if feels deeper than that it's like a little ball under my skin. Is this normal? Thanks! :)