Leaking of sticky substance from penis

Age: 31 Yrs
Sex: Male
Built up:Moderate( Height: 5'10", Weight :- 78 Kg)
I am fond of sports. I do exercise on daily basis.

Excessive leaking of sticky substance from penis when got excited. The situation become worse during last 1-2 months. And I realizing that my penis and erection became weak(it was strong before) and scrotum became flabby now.

In my opinion cause for my problem is starting musterbation at the age of 14.I think this the only bad habit which I have and my present situation is result of the same. I have started this at very tender age i.e. 14 Yrs. I had this habit 7-8 days(approx) in a month upto age of 20 Yrs, sometimes twice in a day. But after that it came down to 4-6 days in a month. Nowadays it becomes 2 days in a month. Whenever I stopped masturbating, it ejaculated at night during sleep.

I have taken Nux Vom 200, 2 Drops, 2 Times(Night and Afternoon) for last 15 days but there is no change.

I am single and I have never had sex. But I think there might be a chance of premature ejaculation and lac of erection as per my present health condition

This is pertinent to mention here that I am going to marry in April'2018. Whenever I chat/talk/meet(never touched her and no illicit talk) with my fiance or think deeply of her this sticky substance is leaking out from my penis. And I am anxious that this problem leads to premature ejaculation or weak erection.

I am very anxious about this problem. Is it curable or not? Kindly help me coming out from this problem.