What was your cycle? Did you run an AI during the entire length of the cycle? If so, how much? Any previous blood work to indicate that your overly sensitive to rising E2?
The mentality that one is "not prone to gyno" doesn't make any sense to me at all. You and thousands of others feel they are not sensitive or prone to gyno simply because they have not grown breasts. And because of this they dont include one on cycle. But more often than not this seemingly small oversight returns to bite them in the ass.
You may feel that youre not gyno prone but your estrogen prone, and your body and endocrine system is prone to reacting to hormone fluctuations and imbalances. And this is what i believe is occurring in many many young (and often older) AAS users who blindly believe that they are "not prone top gyno."
You and many others have developed a false sense of security because most are able to complete a cycle without having grown boobs. This needs to be addressed either with blood work, or at the very least the inclusion of an AI to assist in preventing further complications down the road.