Why Do I Feel Like Passing Out?

I Just Started Working Out This Week, Not Much But At Least One Hour A Day. But When I Am At The Half Of My Routine, I Get The Sensation Or Feeling Like Throwing Up. I Get Like A Gag Reflex Feeling. It's Been Happening Since I 3 Days Now...Is This Going To Continue?....Why Is This Happening? And What Can I Do To Not Feel Like This When Working Out? Thank You For Your Time