Small cyst/lump, pain in left testicle.

From the past few days, I am feeling a very small cyst/lump in my left testicle. Sometimes, I feel like its there when I touch my left testicle and sometimes I feel like there is no cyst/lump present. It also causes sometimes dull pain in left testicle. Sometimes I also feel dull pain in right testicle also but don't feel any lump in right testicle. I am very much scared about it, not able to concentrate on my studies also. I am also feeling like my testicle size has reduced or maybe not working properly, but I am not sure, maybe its a myth. Also, does this lump/cyst and dull pain be caused by excessive masturbation? If yes, please tell me the treatment, I will never do this masturbation again in the future. I am very much scared and embarrassed to discuss it with my parents. I also feel like sperm quality has reduced, but I am not sure of anything. Please someone help me, I will be very grateful to you.