Hi there. Ouch! Bad area to have pain!! Could be as said above, an ingrown hair or could be a cyst. Try not to worry!! I am so glad that you spoke to your mom. I'm sure that if it is still bothering you on Monday, she will take you to the doctor to figure out what it is. Come back and let us know how you are, okay? good luck
if you shave sometimes it could be a ingrown hair and its harmless. just don't squeeze it or try to pop it. have your doctor lake a look at it and just be patient.