Dear service user, I got your question and understand your concern. When sexual arousal occurs, a fluid of sex organs and tiny glands in the way of urine tube come out from penis. This is not semen. The smell of the fluid and consistency may be like semen. This is not a disease and no need to seek medical treatment. Relax and don t worry about it. Weakness and leg pains, erectile dysfunction are secondary to anxiety of your perceived semen loss. I recommend you to read about Dhat syndrome on internet. You may consult psychiatrist for counseling. Short term course of anti anxiety medications are helpful. Wish you good health.