Do I have Testicular Cancer?

I'm sixteen years old, and I have a small lump on my left testicle. It's just below the skin, and it is about 2 cm by 1cm, and about as thick as a skittle. It appears to be purple, and it is located right at the bottom of my testicle. I can safely say that it is pretty new, and it is sometimes uncomfortable, but not terribly. I know that I will not be getting another physical for nearly a year, but at the same time I would like to spare the embarrment of going in to get them checked.