Anorexia or crash diet?

okay so im 13, 5'4 115 lb. i have bad eating habits and i was wandering if its just a crash diet or like anorexia. so days that my parents arnt home and stuff i usually dont eat anything at all. just water or 0 calorie drinks. when my mom cooks dinner i just say i already ate and im not hungry. but when we go out to dinner like at a restaurant i usually eat a normal amount. because i dont want my parents thinking im not eating enough. and then just try to burn as much as i can off by running down our street or doing exercise videos. i am very insecure with the way i look...i always feel fatter then everyone else. even though i weight the same as most of my friends. if i eat anything i will start to freek out and ill just start running around to try and burn it off. losing weight is like on my mind 24/7. i also have an anxiety problem. so some nites i dont even sleep because im freeking out about how i look. i havnt really lost any weight.....but ive only been doing this for about 2 weeks. and when it comes to how many calories i eat in a day...every day is different. it could be 0 one day and 800 the next. i obsess about calories alot....if the box even says 0 on it, ill go back and check at least 4 times....i dont know why i do that though. and the longest ive gone without eating anything was 2 days i think. so ya i was just wondering if you guys think its just a regular crash diet or an eating disorder. i know im not underweight, so thats why i wasnt sure. (&when i dont eat for 2 days i usually go down to about 110lb). any answers would be a big help(: