Is Anxiety Still Anxiety When It's Rational?

I live in a perpetual state of feeling like my entire world is about to fall apart, a constant awareness of disaster looming in the periphery of my perception… I’d love to say this malady is of my own making, that it’s all a figment of my overactive imagination, but I’m almost completely certain that I’m only very slightly exaggerating things to myself, that it is in fact simply reality.