This is my Story and Please dont neglect it :( read and answer it? it is very important for me to know?

See people it happened around in 2005 when i was around 14 0r 15 and my brother(cousin) was around 12 0r 13 years old) i had reached puberty to ejaculate semen but he hadn't reached.We had homosexual relation for one day and i ejaculated semen on his penis and then after that we tried to have sex but we were not getting privacy and time went on and nothing happened again like sex.So in present year or month his(my cousin's father's brother's son is found hiv/aids positive and he is being treated for that and he is 13 years old right now so now i am in thinking process can i get or have aids if this is the situation. Please read it carefully as only i ejaculated semen not my cousin it is been 6 years when it happened There was no bleeding from both of us there was no secretion of any kind from my cousin as he hadn't reached puberty."