pimples near vagina?

okay so i’ve been getting pimples ( what i think they are ) on the side of my vagina where my leg is and the first time that i popped one, it was all white and was hard. the second time i popped one it looked like something black was in it mixed w white and it was also hard and this one that i just popped now was just white juice that squirted out. can somebody please tell me why i keep on getting them and how to make them stop coming back??