I'm tired!

I'm really tired these days. I didnt get enough sleep...either i was worrying about something or i had something to do. I just so much to do and at times saying "No" is hard. Well, sometimes when i said no, people turn away from me or saying sumting bad, not appreciating that I've really considered everything. I cant do everything! hoh, so frustrating. Why do i care so much of what people think...and why do i afraid of them...ughhhh.