What Causes Nocturnal Emissions?

Hello sir, i am 28 years old guy, During the age between 15 to 22 , i have frequent wet dreams, sometimes 2 times a day. but with growing age now its become less, but due to that frequent and excessive wet dreams, i suffered from constipation and also feel the hotness near the left down of belly, Currently also i feel some mix feeling of hotness and coldness after the wet dreams. Is there any intestinal infection occurred due to the excessive masturbation and wet dreams. ? Between these i started zincovit tablet for the weakness,, it helps me lot for a year, but after that i feel acne and gas problem just after taking the zincovit, is that due to overdose of zincovit, ? please give me reply regarding this and suggest me a good vitamin supplement that does not produce heating effect in my stomach or intestine and also not give side effect like constipation.