I am 19 years old .Once when my penis was erect I found a sticky substance forming a layer on glan of my penis .Although it does not cause any pain and I removed it also but only to find that it is also below the glan(neck of penis) and it keeps coming again and again .I am asking this question because I am scared as to what is it and also because when I go the doctor for consultation what do I tell him specifically. I will attach the photo of that tiny substance it is kind of dry because I removed it from glan long time ago and also I do masturbate weekly twice or tgrice