What specific symptoms would you suppose would be associated to having both? For years I've suffered from headaches and I feel the cause is almost always a lac

What specific symptoms would you suppose would be associated to having both? For years I've suffered from headaches and I feel the cause is almost always a lack of oxygen (I suppose) to my brain. I've realized I definitely suffer from shallow breathing and over the past few years I've learned to breathe deeper. It has definitely helped a lot, though I always wonder if there's something else.