Inappropriately frustrated:
anything and every thing makes me explode with unnecessary bouts of anger or aggression. Examples: if I get hurt just a little I will hit myself or punch what ever hurt me. If I can't do something I get so mad I will scream or bite me hand or even smack myself repeatedly in the head. My friend knows how easy I am to push over the edge so she will purposely poke or even barley touch my skin or do something very little that I don't like at the time after I've told her to stop until I eventually lash out with yelling and hitting her. If an object doesn't work the way it should the first time I will get so frustrated I try to inflict 'pain' on a non living thing. When I express outburst of anger I get more angry because I'm acting so inappropriately and I hurt myself more and tell myself I'm stupid and an idiot. I feel embarrassed, mad, upset, frustrated, and my body becomes uncomfortable when I have the random explosions. They happen everyday and most times I don't have signs they're coming. My body will feel like it needs to be pulled all direction kind of like I'm stuck inside my own body or my limbs aren't long enough for me to fit inside myself. I'm 19 years old and this problem has been getting progressively worse since I was about 8-11 years old. Even as a child I couldn't handle anger so I would take it out on myself instead of others I would claw my face and arms. Smack myself. Pick scabs. Bite my hand with as much force as my brain would let me. I explode in mean nasty manners with people who know I have an anger problem like friends and family I could be perfectly fine by myself doing something that was calm and without stress and my mom or sister or friend could ask ne a simple yes or no question and I will snap and be rude or hateful. I feel horrible after which makes anymore mad and I literally have to clench my teeth to apologise and when I do apologise my body gets really tight even though. I'm aware I'm in the wrong. I have problems also with people showing intimacy or love towards me. Especially family. It makes ne feel uncomfortable or mad they are showing me this. I can barly say the word I love you to family it all depends on the day if I can get myself to say more than you too back.sometimes I won't talk but a little to friends and family. Distant friends and people who don't personally know me think I'm crazy when I tell them I have anger issues. I'm known to be funny outspoken and fun to be around.( Even my close friends think this they just pass my weird outburst off. I know it scares them sometimes not for there safety but for mine.)i have many friends and I'm easy to get along with and easy to talk to and I get average grades.I only have a handful of close friends and only one or two have seen my emotional problem full fledged. I'm scared of my hidden identity or personality. I don't have a name for its not multiple personality disorder and I do talk to myself in third person but I don't hear other voices so its not schizophrenia. I am starting college soon to become a clinical psychologist and I'm scared I'm to messed up to be a good one. I need help.

Instead of trying to self diagnose... have you actually gone to a psychiatrist or psycologist to have someone objective evaluate you?

With a lot of expensive testing, you may find that you have a physiological basis for this. It could be anything from a head injury, roller coaster whiplash, type of seizure disorder, or something on the autism spectrum. I don't know if the science isn't there yet, or if it is but it's just not easily available to most people without going to one of just a handful of medical centers in the world. I would shop around for the best doctor you can find, for starters.
If you think your behavior has to do with just childhood experiences, then find a good therapist for talk therapy.

Even rarer still are dietary causes. But please tell us - have you ever had a head injury or whiplash?