Breast pain

Hi everyone. I am 22 years old and have been having breast pain in a specific spot in my left breast. This has been happening a couple weeks now, it will go away for a couple hours, but come back. It is on the side, next to my armpit. I can't feel a lump, so does anyone think I should be worried? Should I schedule a doctor appointment or not worry since there's isn't a lump? Thanks in advanced