It's been a while

I feel like I'm literally losing my mind. I can barely think or breathe. I feel anxious and constantly unsettled and I have trouble thinking positively. I feel like I don't know who I am anymore. I always feel sick to my stomach. Thinking of the future literally scares me to death. I can't focus or function at all. I JUST WANNA KNOW WHAT TO DO NOW. Someone please tell me HOW everything changed so fucking fast and out of nowhere. How am I supposed to keep the same when everything has changed. More importantly, how am I supposed to change and keep up when I liked myself the way I was? I don't know how to keep moving on with my life without losing my whole self. I don't know how to still be the same person when almost everything has changed. I don't know how to still be happy. I don't know what I'm supposed to do about anything. And I don't know what to even do about that.