hi..thanks for writing..i have understood your concerns.. you do not have any illness.the semen discharge in the sleep is because you are not masturbating.. our body has glands that have limited capacity for storage of semen, so when you do not masturbate for more than a week, it will overflow and come out at night during sleep when erection occurs, during excitement or during passing urine or stool when abdominal pressure increases.. so it is normal physiology and nothing wrong with you..it happens with every person who do not ejaculate either by masturbation or sex..so dont worry.. the reason for your decrease appetite, weakness and low body weight is your anxiety related to sexual problems,,and actually this makes you depressed.. night fall has nothing to do with heavy work or exercise..so dont correlate it with night fall.. you shud consult a psychiatrist or sexologist about your problems and ask for help.. if you masturbate regularly, your wet dreams will go away and you will start feeling active again.. do not believe myths about masturbation, penis size and sexual problems prevalent in the community.. i hope this will be helpful to you..best of luck..