As i have increased my cyproterone acetate dose from 50 to 100 mg a day, i feel pain around scrotum/testicles. common or normal? and why?

Not normal: It isnt normal for patients to increase their doses of controlled substances without physician input. And testosterone will affect teh testes.

Overdose: The usual dose for people with low T is 100 mg/week thus you are way overdosing and the side effects are not unexpected. I suspect that you are using it to bulk up and the use of testosterone without low testosterone level is not a good idea since this may cause long term damages to your body for transient gratification. Your testes will likely shrink with prolonged use.