This can be a much bigger problem than you think, especially if like me you have low blood pressure. As you dehydrate your blood pressure drops more and more. It's been a problem with me all my life because I often don't realise I'm thirsty and I forget to drink.
Drink water, just plain water.
I got told to measure blood pressure and it turns out mine is low too, so yeah, same problem.
Are you on a ramen and coffee diet, with fasting in between?
Fortunately not ramen any more, eating food not prepared at home gave me all sorts of issues, so yes, I cook and include meat and vegetables and don't fry on lots of oil. Home cooked meals have a lot better ingredients.
Caffeine is an astringent. That means it pulls water from the brain, the kidneys, the cardiovascular system, etc. It causes vascular constriction. That's a fancy phrase that means it narrows your blood vessels.
Oh, I knew that caffeine is a diuretic and that it causes quicker dehydration, but if it causes also blood vessels to comstrict, that can explain the dizziness and fainting.
You need to perhaps take 2 mg of melatonin at 8pm each night. School is for school.
My sleep is fine, luckily. I go for walks everyday and sleep at regular times and 9 hours.
Do you have a meal plan with your school? Set a goal to eat breakfast and dinner at least, every single day. Lunch is optimum too, but a few bites of an energizing snack is acceptable. Think oranges. Or veggies with hummus. Minimum.
I eat two times a day at worst, but that's too few times for me, I feel best with 3 or 4. I need to eat more regularly, but I somehow can't figure out how to do everything and be on time.
For example, yesterday I woke up after 11 hours of sleep (I don't think I woke up in the middle), had to sit for a bit with a coffee and I was already shaking from hunger, because the previous meal was a large dinner (rice, meat, vegetables) at 7pm. I ate scrambled eggs with 1.5 slice of bread, rode the stationary bike to wake up, took a shower and I had to get ready and leave. I have classes in the afternoon. I began classes at 3.30pm and finished at 6.30pm. I ate pasta with chicken near home at 7pm and 2 sandoches for supper and didn't have the strength to do much else in the evening: shower, film, read something, went to sleep. Someone told me to pack lunch (the same rice meat and veggies as 2 days ago) on the previous day, because the scrambled eggs and 1.5 slice of bread until 7pm seemed to be the problem according to him.
Lunch is optimum too, but a few bites of an energizing snack is acceptable. Think oranges. Or veggies with hummus. Minimum.
I'll think about it, thank you. It seriously didn't cross my mind that a snack might be worth eating at home or taking.