Your story has many elements in common with many of us here.
Mine were quite round and well formed even though at the age of 18 and height of 5'10" When I graduated from High School and went into the Air Force I weighed only 135 lbs. Basic taining and the communal shower was a dreaded experience made easier only by the fact that We had another guy in our unit who made a better victim. I had been a wrestler and grew up in South Central Los Angeles; I did not make a good victim at all unless someone wanted to get hurt.
After Basic Training, I went to a Medical Technical School so my associates were a better class of people and better educated as well so the teasing and torment diminished greatly. Even then though there were some events that I'd prefer not to recall.
You did not give your height so I cannot relate your weight to any kind of scale. It might or might not be a issue in any case.
In my case, Gynecomastia seems to be a family trait passed down from my Mother's side of the family. I've not seen any good information to either support or refute a family connection, but it seems to be so in my case. For most men the cause is usually listed as "Idiopathic". The term Idiopathic has been jokingly defined as a medical word meaning "Your guess is as good as mine." In short, the most common cause is: I don't know.
You are fortunate to have been born at a time when safe, reliable and effective surgery is available if that is your desire. At the age of 74, I was born about 50 years too soon.
Everyone at this forum is here for the same reason, so you are among friends. Feel free to speak your mind. Welcome aboard.