I am white...

I really do seem to feel more energy after I have gotten some sun, that is why I was curious about the vit d thing.
My dad and brother have sleep apnea...I am terrified that I have it. But I don't normally feel this way. When I have been getting enough sleep, which for me is 8-10 hours I usually am fine for the whole day...I sleep good too. DH says I don't snore, and the last few nights I felt like I had gotten a REALLY restful sleep, like I don't remember waking up much.
I'm wondering if 2 things are contributing to how I'm feeling. One is AF...my iron runs low during AF, since I run low on iron as it is. And the other is I am coming off of drinking caffeine/aspartame everyday. I stopped doing this, and I wonder if that's effecting it.
Anyhow, thanks for your suggestions.