Maybe it were the hormones
Ya know, around that age you gonna start becoming a man, things like that. And nowadays, in this society, others boys around that age expect from you that you act cool, keep yourself strong, behave like a man. And crying isn't exactly a sign of strength.
I remember when I was 12, my friends told me that it's cool to have a girl. Yeah, they acted so tough, but I don't think they were so cool from the inside.