Suggest Remedy For Painful Strenum Between Breast

Hi, I've been having a sharp pain on my sternum, between my breast. It is sometimes sudden and at other times its a slow dull pain. I can pop it and it'll feel better. However it has been more frequent as of late and I am concerned. I'm jobless and can not afford right now to go a see a doctor, is this something to be concerned about and that I SHOULD go see a doctor for?