Hi I Had Concerns About A Lump I Have On

Hi I had concerns about a lump I have on the shaft of my penis I had sex with my girlfriend New Year's Eve and masturbated New Year's Day I then woke the next more to a bump on the side of my penis my first action was to drain the fluids and allow the scar to heal itself but less than a couple minutes a lump appeared.....it has been almost a week now and the lump seems to be getting bigger and is consistently warm and tender to touch it is causing me a lot of pain and discomfort but I don't want to make a trip to the hospital or clinic if it's not needed... thanks hope someone could shine a light on this situation for me