Prostate stinging pain. Tests clear!

It all started 1 year back I was sleeping at night, when suddenly my penis and lower abdomen started unbearable pain with stinging sensation starting from center stomach ending to Penis. From that day it doesn't stop. Now the pain is happening 3 time in a weak maximum on night. And then regular presence of the pain can be found when I do urine from myself and the urine comes to end the pain starts in Penis remain from 10 min. And that day It will definitely pain on night. And pain also start on pressure stool. My assumption the pain starts from prostate. Note- I have regular gas problems stool problems Masturbation habits Taken levotas500 for 6 month but pain period slow down but problem doesn't go Urine culture clear Ultrasound clear Tc DC other tests clear