Question
hey doctor wen i was 13 i realized i had a lump on the middle of the back of my neck near the hair line ,when i first realized  it it was small but throught out the months i've had it it grew. i have no idea what cause it but every month for like 3 day it has this sharp pain
by any chance do you noe what this is

Answer
Since you didn't have an accident, we know that it's not a neck injury.  I would recommend that you see a doctor that can examine you and take an X-ray to see what's going on.  It's really impossible to tell on the internet.

Thank you for your question, Emily.  I hope that my answer leads you to some help.