What Causes Pain In Testicle Along With Ejaculation Problem?

I will like to know if lack of sex has any effect on the body, I recently got sexually active after a period of 6 years. I ve noticed some pain in my left testicle, also my ejaculation has been somewhat weird there are times I cum very quick and there are times I don t cum at all despite all efforts by my partner. I want to know if there s any information that can help or explain what I m going through. Thanks