Is there anything wrong with me?

Well i often draw away from crowds,well any one.I don't like making friends because most of the ones I've had abadoned me.I do activites like writing stories,poetry and I listen to music.I mean i seem happy to most people's eyes.But its hurting me to keep pretending.I put on fake smiles half the day and wish i were dead the other.I aslo barely speak to my family or the few people who actually like me.I can never open uo without shedding many tears.And i find myself crying myself to sleep in the middle of the day.Its not even the pain from my constant falling,scraping and all the other bruises i get in between each day.Its the inside of me that makes me think about suicide.But some days I can be so happy then one minutes later I can feel depressed.I sometimes cut myself.And it helps.But poetry does more.No one understands me at all.I feel so alone in this world.What's wrong with me?