I recently noticed an abnormality in my testicles when masturbating a week or so ago. Midway through, i felt a small lump on my left testes. On further inspection i realized that it wasn t attached to the testes, but rather where the veins were located. I feared the worst thinking it was cancerous, but after researching it seems as if it is varicocele. Does this flare up after masturbation, as whenever I have done it in the past week, I notice the vein gets more noticeable and after a time goes back down into a smaller lump.