small "bruise" on back

I've had this small bruise on my back for about 1 year or longer now and it hurts mostly when im on my period but it still hurts 24/7 if i push on it. It doesnt look like a bruise exactly but thats the only way i can explain it. Its about the size of a pen tip maybe a little bigger cause i can see it in the mirror and in pictures. I cant just go to the doctor because i have no insurance. Last time i posted this question, i got 1 answer that didnt help and then Yah** deleted it! Someone give me real opinions, im quite worried.

also, about 2 weeks ago while i was on my period i went to get out of bed and my back (right where the "Bruise" is) It hurt so bad i couldnt continue to get up or even lie back down. So i just dealt with all the pain and went back to sleep. Tweet