Hi. Thanks for your query and faith in us that you shared your problem on this platform. The pain in the testicles on touching the tip of the penis is a over-reaction of a natural process. Do not worry about it. This occurs due to over-stimulation of the Dartos muscle covering the scrotum, the cremaster muscles of the abdominal wall going into the scrotum to support the testes. They are contracted and the hormonal changes in you cause congestion in the testes. Try to masturbate and have sex, you may get relieved.