Hi, I'm 18 and just had surgery on my groin due to a torsion. It has been about 4 weeks now, and i have discovered a hard ball that stands out when i look at it from the side. If i feel it I can move it around. I have no idea what this is. I have 4 weeks of stress.
Since the lump seems to be related to your recent surgery, the first step for you would be to go back to the surgeon who performed the surgery. S/he should be able to help you. Often a testicular ultrasound is the best way to get an idea of what's going on. These are the two things which I might recommend (i.e. visiting the surgeon and having an ultrasound).