Mass ? Or Cyst ? Tumor??

Have any of you ladies ever had a mass or cyst of some sort come up out of no where on your vigina !?! It's not a sore ... It's not like a pimple or razor burn or even a ingrown hair this is like a knot up under your skin like a rock or ball or marble or something like that ... Just pop up out of no where ... ??? Not on the inside of my vagina but on your outer lips like the labia majora .. I had 2 pop up last night on each side in the same exact spot !!! Then today I've had another one pop up on the left side above the other one.... What could it be ?? Has anyone had this happen before ??