Do I have a problem? im desperate for some advice so please answer seriously :(?

I'm 16 years old, 166cm 49kg. I'm scared I have a problem, maybe an eating disorder or depression or even both? I weigh myself about 5 times a day. I'm obsessed with my weight and i always think i look fat and i hate myself for it. I never wear tight clothes because im ashamed of my body :( i always compare myself to people i see even strangers and always think 'i wish i could be like them there so skinny'... i hate it and i always get very depressed and cry a lot about it. I always watch what i eat and count calories and fats and carbs and restrict my diet as much as i can because i want to be skinny. I exercise almost every day btu not for fun i force myself to go running to lose weight. I'm always so tired and lacking energy and my school works getting really bad at the moment because i just cant concentrate :( i just hate myself at the moment and im scared maybe the reason i feel like this is because i have an eating disorder? i dont have much experience about this kind of thing so i really just want to know whats wrong with me cos i never use to be like this it only happened a few years ago but the feelings have just been getting stronger ever since :( thank you xx