Heartaches of a 13 year old...?

Latly I've been feeling a little down...I feel like no one really likes me and all of the suddent for know reason I get angry and sometimes I even yell at the people I love and I say mean things to them. One min. I will be fine and the next min. I will feel all sad and teary. And my heart it hurts, it actully hurts, like someone is squzeing it lightly and the feeling is kind of comeing up through my through. I'm being really moody to, one moment I will be like "I'm never eating again" and the next I will be stuffing my face (even if im not really hungry) I feel tired and drained of enegry I have been haveing very...uneasy thoughts...What should I do? I am only 13...is this normle?? What can I do to help this?? Nothing really bad has happened in my life for a while...