How can i stop thinking this?

My mind right now has been chaotic for the last couple of days and also sporadically since around late-Feb. Yes, you can say I am growing up, but it's like the fairytale suddenly ended. My mind is changing, and at the same time, it is unable to get over the problems in life that are supposed to happen. I keep asking: "Why did this bad thing happen?" "Why can't everyone be happy?" whatnot. It's really giving me a whole new meaning on life and living and doing something. I am constantly worrying about my family, myself, the future, uncertainties, it's overwhelming. Everything I've worried about in the past seems petty now. I'm just in a quandary that I never thought I would come to, and how differently I look at things now. What's going on?