Immediately after my first orgasm during which semen was released, which occurred when I was around 12.5 years old, I began to feel extremely sad for no reason. Before the orgasm, I had been masturbating and "climaxing", without expelling semen, for around 11 years without any noticeable symptoms. By the way, "11 years" is not a typo; I began to fap at an unusually young age. Perhaps that caused my POIS. My POIS started when I was first able to ejaculate semen, leading me to believe that the cause of the type of POIS that I have is related to seminal fluid.