Hey there bbb, the short answer to your question about hangovers from CH.... ABSOLUTELY. You don't mention what pharma your taking, in my experience, if you are trying to "tough it out" with nothing, experiencing a KIP 8-10 CH, my cognitive processes were shot, I felt awful (hungover) and it would last for hours. My neuro's explanation was... chemicals in the brain are released during CH, this is the hangover.
For me imitrex injections worked GREAT, abort the CH and no CH hangover. There's a lot written on this site about triptans. I keep them close, but now, with busting, O2, D3, they don't get used very often.