I have a very long refractory period. After I have sex, it takes me 4 days to want it again. After 4 days, it's all I can think about. But after I have sex up to 4 days, I don't even want to think about it. You can imagine, this screws up my relationships. I'm not so old that this should be happening. It's been happening for the past 5 years. What can I do about this? What is causing this? My testosterone levels are ok according to the doctor.