Feeling depressed, unwanted, hope less, lifeless, and empty..?

im having one of those days, where i just feel like crawling in a hole and dying, i feel empty. i have no motivation to anything but lay under a blanket, and not talk to anyone, i don't know what to do i don't want to talk to anyone about how i feel, i don't know what to do anymore, the "bad days" are becoming more frequent, the days when life just feels hopeless, and worthless, I'm 15 i shouldn't be feeling this way.. what should i do?