Thanks for asking. I can understand the distress you are through. Your problem is suggestive of "Dhaat Syndrome", a presentation of premature ejaculation problem. There is spontaneous discharge for semen in urine. With suitable medications it can be completely cured.
Next Steps
Kindly consult with a sexologist for further management. For medication you can also consult a directly here on practo.
Health Tips
Don't worry. It is completely treatable problem.