I screwed up. Tractor is parked at the back of the barn, 60' from front doors, usually when I start it I have those doors open and the man door at the back open to create a cross ventilation. Temps were below zero and there was a north wind hitting the man door so I did not leave it open, opened the front doors as usual and started the tractor. Decided to change angle on the snow blade so I pulled the pin, long story short I had a heck of a time getting the cotter pin back in. It was so cold that my hands were just not cooperating, this resulted in me being in the exhaust output for a period of time. Later that night I started getting a headache and it lasted all the next day and is just now easing up. Could breathing the exhaust cause the headache? If so is there any home remedy? I have had the Shiatsu massager and heat on, took Ibuprofen, but none of that made a diff.