i've been dianosed with depression since i was 7. i am 16, 17 next month.
from what you described sounds like you are depressed. or it is possible you have depression. also another thing it could be is SAD which stands for seasonal affective dissorder. thats what i was first diagnosed with. it means you get down and depressed during a certain season, which in your case would be winter.
what i suggest is talk to your parents about it and make a doctors apointment. you can talk to your doctor about it and they can either prescribe you anti-depressonts or refer you to a phsyciatrist, or counceler.
i hope this helps!
if you need to talk, you can PM me