I am sorry to hear about your symptoms, and I can certainly understand why you are concerned. In order to provide an accurate recommendation, I would need to review your entire medical history and also perform a thorough physical exam, including a testicular exam. Only after collecting this information would it be possible to comment on a likely diagnosis. I strongly encourage you to see a primary care physician
to discuss these issues.
Testicular lumps can be benign tissue growths and can also be part of the normal testicular structure. For instance, the epididymis, or series of tubes that help transport sperm, is often felt as a lump on the posterior testicle. As you mention, a lump can also represent testicular cancer, and you may require an ultrasound of the testicle to evaluate this further. It would be very atypical for prostate cancer
to develop at your age, and it is extremely rare for it to present as a testicular lump. However, you will need to discuss this with a primary care physician.
Frequent urination may be unrelated to this lump. Frequent urination can be secondary to diabetes. A urinary tract infection or infection of the prostate (prostatitis) can also cause frequent urination. I encourage you to raise these possibilities with a primary care doctor