I'm Not Sure What's Going On, About A Month Ago

I'm not sure what's going on, about a month ago my penis started itching badly, the itching spread to the inside of my thighs, then I noticed a painless bump on my testicles, a few days passed and I started gettin red spots on my penis head, I had sex with my girlfriend a few days later and the red spots rubbed off and became painful. Now it's like a black scab, it's been two weeks since then and now the red spots on my penis head are starting to fade away but the black scab is still there but my penis head has very flaky dry skin and very itchy. It itches very bad after a hot shower and at night when I go to bed. The first bump on my testicles I mentioned before disappeared, but Now I have about 13 of the bumps on my testicles and they are itchy also. My hands are itchy they have clear little clustered bumps that pop and clear fluid comes out. My arms also itch! Help me!!