lol bro Im the same way since I always lift heavy. I will try something for 12 reps and I do 6 and it feeels like Im gonna get 20, then all of a sudden its like I hit a brick wall and literally goes from easy reps to one hella hard rep and then i cant do another one after that. lol it sucks
I also LOVE eca. I believe its bad for u though, but I do love it for energy