Can a non-blister pimple on penis shaft be normal?

Visit your doctor for proper analysis of your report.

You may have a yeast or bacterial infection based on the signs you mention. These microorganisms can make one double over with pain, pee mistakably, and release a mushy white discharge. Hygiene is always a requirement in the area and should always be kept dry. You may require medication to treat the infection. Stay hydrated and avoid sweet foods.

You might have encountered testicular torsion, a condition of the testicle that twists and cuts off blood supply. This is an acute medical case and you should immediately see a urologist. 

You may have a condition called varicocele when the veins in your testicles are enlarged like the varicose veins in your legs. This can cause a scrotum that is swollen or heavy to feel. The epididymis is a coiled tube located behind the testicle, and it can also become inflamed, leading to pain and swelling. Varicoceles and epididymitis don't usually lead to serious problems, but it's important to see a doctor to confirm the diagnosis. The doctor might recommend wearing supportive underwear, taking pain medication, applying ice packs, and sometimes surgery in severe cases.

Regarding the size, an erect penis of around 4 inches may be enough for some people, but it varies. Premature ejaculation can happen for various reasons. It's best to consult a healthcare professional for personalized advice on both concerns. Communication about preferences and needs with your partner is also important for a healthy sexual relationship.