Hamstring problem

Hi. I have a question about my hamstring. I hurt it 6 or 7 years ago playing baseball. I was running the bases not hard when I felt a pain. It was not that bad of a pain, I figured it was a strain. I came back acouple of weeks later and tried playing and the pain was worse, but not to the point that I couldn’t walk. There was no swelling and very little black and blue. To this day I still have a golf ball sized lump in my lower hamstring when I flex it. Above that lump is a huge divot. My questions are: is it a tear, or a rip? How can I fix this? Thanks,