Dehydration causes this all the time- that with the other factors of poor diet, tobacco use cutting down o2 intake and we must remember that the water travels with o2 in our bodies.
Low blood sugar can easily be treated by paying attention to what you eat- natural sugars only and always having some calories on your stomach- 5-8 small meals a day instead of 1-2 large meals a day.
Red Bulls not only dehydrate you- they fuck with all your chemichal balances, those within the body for homeostasis and those within the brain that allow us to 1. be able to place our selves within time and space and those that regulate and control mood, emotions and thoughts.
Hydrate, hydrate hydrate!
My ole time doctor daddy always said drink a gallon of water a day- if your still feeling bad make funeral arrangements. Adequete amounts of clean fluids daily go a long way to improve our health and our brain functions - the brain is 70% sugar water- dehydrate that and don't allow enough natural sugars to it and it will start to deteororate quickly, and cannibis can't really help you with that - but probably didn't cause these symptoms...
Oh yeah....the tilt test is important - it tells the physician how hydrated you are in the moment. You can do it yourself at home sort of. Lay down on the bed for a few minutes, then sit up quickly - at the doctors office they will take b/p and pulse at this time- if you get lightheaded or dizzy in any way you very dehydrated and need fluids!