Info about fighting (melee)?

Ok i've been getting hit since i was 2yrs old i learned how to fight when i was 3yrs old but would never hit anyone as hard as i could cause i didn't want to hurt them but when i was nine this kid kept hitting me in the face over and over while i was on the ground until i heard my neck snap and then it felt like my muscles turned into pads and i couldn't feel anything but i got this sudden urge to hit him but what was weird was i knew where to hit and it felt like every hit and step was planned and ever since that day when ever i fight i know where to hit how hard to hit how many steps it'll take and how long it'll last which sounds fine except when my body goes on auto pilot cause when it goes on auto pilot which it almost always does i hurt people way worse than originally planned so what i'm asking is 1) why do i have an auto pilot.2) how do i turn it off.