Why do I feel nauseated and have a headache?
I wish I could help you but there are so many things that can cause nausea and headaches. Why don't you see if you can be more specific (are there any other symptoms?) and try the Check a Symptom box on Health Central and see what it tells you. It could be some sort of headache, a virus, a reaction to pressure changes, or due to something you've eaten. It's really hard to know.
Here are some links that might be useful to you:
7 Ways Your Body Says You’re Stressed
Cooking to Control Pain
10 Chronic Pain Myths