It just hurts and i don't know why?

It just hurts for me to do anything, it feels as though an icy sword has just stabbed my heart. Any time i see something good or talk to someone i just feel it. If i feel sad, i feel as though im burning and i just want to crawl in some time space and never come out. The numbness, the pain is almost unbearable. I don't understand it. I continually feel light headed, and i just can't take stress. I have no idea whats happening to me. There's nothing going on with my life, the biggest problem i probably might get is breaking a nail. Any ideas?