I went through a period like this when I was younger. Try different positions masterbating, if you can masterbate easier lying down or sitting or even try masterbating while lying on your back with your legs open (like your upper body is lying down but your pelvis and legs are in the "indian style" position). After a number of years it turned out I had pudental nerve entrapment and the impotence or numbness, in my case, was caused by increased pressure on the pudental nerve (nerve to your penis). Most doctors I saw attributed it to stress or pelvic inflammatation-which you might have also. In my opinion a doctor should check your hormone levels, then try a trial of Antibiotics for pelvic inflammatory disease, if your problems persist and especially if you have pain in your penis after an orgasm or your penis gets unusually cold after an orgasm (sign of nerve trauma), I would set up an appointment with Stanley J. Antolak, Jr. M.D. at http://www.centerforurologicandpelvicpain.com/
. It may be out of state but hes the best Pudental nerve entrapment doctor in the U.S. He does injections around the nerve to free it up/reduce scar tissue and if that doesnt work there can be surgery (very safe). I hope you find relief. Email if you want feedback
Charlesbeut@hotmail.com