Yes it is from the lack of oxygen. the pursed lip breathing does help with the headache

I have a O2 meter on my phone. I check it all the time. I'm not on O2 yet. Go to the Dr on Monday. Thanks everyone.

I think the same the saturation must be low. I just bought a. Meter that will give me my oxygen levels. You just put it on a finger they use them in the hospital.

I was thinking along the same lines as Jean. Maybe you oxygen saturation is low.

If I get dehydrated I get headaches,especially with even moderate exercise. Always water, coffee and tea doesn't count.