I suffer from anxiety on and off but lately i feel like once in a while a random thought comes in my mind about "what if something awful happens to me" and all of a sudden it gives me the sinking feeling in my stomach i feel hopeless it feels like some one just give you the worst news about your like e.g it feels like a dr just told you that you had some horrible diseases and it makes you feel like your life is over you have nothing to look forward.

Does any one else feels like that it just makes me very depress usually goes away on it own. Is it anxiety or depression