I need to know whats wrong with me and what should i do?

ok so i just got into some deep **** and ive done alot of thinking and there is somthing wrong me i know. me and my friend stole his moms car multiple times and we got caught becasue some skank ratted us out! im about to kill her, all i can thhink of doing is going on a killing spree and ending everything right now. i also have a hard time paying attention and sleeping. i have big mood swings but there not like bipolar intense mood swings. i usually dont feel emotions or feel bad but i do occasionally. i use to cut myself a little bit and i love being burned! whats wrong and how can i help btw im 14 and a boy