I found it was my oxygen going low through the night.Hope you feel better soon.COPD is life changing.I’m finding it harder to breathe but my lungs are clear.I can’t walk far,just waiting to have more tests.Take care from 🇨🇦

Sometimes morning headaches are caused by elevated Co2 levels in your blood. Ask your Dr about it.

Low O2 sats during sleep can lead to morning headaches. I'd ask for an overnight oximetery test to see if you need O2 at night. Many of us do, because we breathe shallowly at night and don't get air deep enough into our lungs to stay adequately saturated.

Could be not enough to drink. Your body empty all it waste water from your legs as its hard for your heart to do so. So keep a drink by you bed and have a few sips. It might help. It did me a lot.

In my situation I had the problem with my crap and then I raised my oxygen I hope that helps. I also went down to the pharmacy and purchased one one of those oxygen meters