If you have a cough and a headache -- like as if you have a fever but don't -- then you probably got a bit of metal fume poisoning.
It goes away in a few days. But it probably isn't great for you.
A respirator really works to prevent this. It can be a little awkward under the hood, but if I'm TIGing anything which might give off vapors then it's worth it. These include galvanized metal, chromed metal, and brass.
Chris