Has anyone here ever experienced panic attacks on a testosterone cycle? I have never experienced panic attacks until I was about two weeks into my first test cycle. Had about 3 episodes were I had a rapid heart rate and fear of a heart attack. They were triggered mostly after a workout or out of nowhere. Had to quit cycle because of it. Can anyone give an explanation to why? Could it be too high of E2? Also my cardio went to shit. It would feel like my heart was working too hard and had heart palpitations.