Is emission of semen the only sign of puberty?
Question

                I am sixteen years of age and all of the signs of puberty have appeared except the emission of semen. Is this a sickness or is it something natural? Please note that my basic diet is vegetarian.
Praise be to Allah.
    Puberty has signs which are well known for both males and 
    females. For a male, puberty is reached when one of three things happens: 
    the emission of semen, the growth of coarse hair around the private part, or 
    reaching the age of fifteen. 

    For a female, puberty is reached when of these three things 
    happens, and there is a fourth sign, namely menstruation. 

    It is not essential that all of these signs appear, rather 
    one sign is sufficient to establish that a person has reached puberty. 

    See: al-Sharh al-Mumti’, 6/202. 
The fact that you have 
    reached the age of sixteen indicates that you have reached puberty, even if 
    no semen has been emitted. 

    You should note that you are now mukallaf (accountable) and 
    are responsible for your words and actions, as the Prophet  (peace and 
    blessings of Allaah be upon him) said: “The Pen has been lifted from three: 
    from a child until he reaches puberty, from one who is asleep until he wakes 
    up, and from the insane person until he comes to his senses.” Narrated by 
    Abu Dawood, 4402; al-Nasaa’i, 3432; al-Tirmidhi, 1423; Ibn Maajah, 2041. 
    classed as saheeh by al-Albaani in Saheeh Abi Dawood. 
We asked a doctor about 
    your situation and he said that it may be the matter of sickness, or it may 
    be something natural, so you should refer to a specialist doctor to find out 
    what is going on. 

    We ask Allaah to guide us and you. 
And Allaah knows 
    best.