My Hair Smells Like Ammonia After I Straighten It And

My hair smells like ammonia after I straighten it and take a shower. In the shower it smells like a smoke bomb. The stench stays in my hair for a week. I always wear my hair up because putting heat to it makes it stink. I just paid for an chemical poison test and came back negative. My hair has been like this for 2 years now. I don't know what to do.