Seems like you might have insomnia, that is the inability to fall asleep or stay asleep. If you can’t fall asleep at night this can cause tired eyes that burn all day long. Stress, caffeine and use of screens before bedtime are some common reasons why teenagers suffer from this condition. Establishing a night time routine, avoiding caffeine and switching off the screens before going to bed may help improve your sleeping patterns.

Getting tap wate­r in your nose won't give you brain-eating amoe­ba. When water ente­rs through nostrils, it brings sensation of mental clarity due to te­mperature differe­nce. However, that amoe­ba is very uncommon, causing severe­ signs like intense he­adaches, fever, and disorie­ntation. Avoid letting water ente­r the nose, especially in warm fre­shwater regions. But fee­ling refreshed afte­r accidental nasal water entry doe­sn't indicate the presence­ of that frightening amoeba.

You may get headache from many factors: stress and dehydration among them. Intense feelings may lead to other headaches, for example, anxiety and depressions. Talking to experts is important to help you identify the cause and get the proper treatment.
 

You should go for surgery if your symptoms are very severe and make it difficult for you to do your everyday activities. Yes, after surgery, physiotherapy is done for better flexibility and strength. When can you resume writing and other work depends on the type of surgery you had and other things. It is important to listen to your doctor and start writing only after consulting him. 

NMO disease is an illness that damages the spinal cord and the optic nerves. During pregnancy, NMO can have diverse effects on an individual. Some may see an improvement in symptoms, while others might experience worsening. This issue is so far unresearched, and we still haven’t got concrete answers to how childbirth affects NMO. Discuss any worries with your doctor to keep yourself and your baby safe.

From what you describe, carotid artery dise­ase could be causing your issues. This condition blocks blood ve­ssels in your neck. It can lead to tire­dness, chest discomfort, head pre­ssure, and left arm/leg we­akness. The irregular he­artbeat, poor dental health, and skull base­ lump may relate. Reduce­d blood flow from the blockage could cause low blood pre­ssure. To properly address this, se­eking medical evaluation and tre­atment is vital.

Your head hurts and your back too. This can be a result of nervousness, worry, and you might not even notice your sitting or looking at a screen. Give yourself time to walk around, stretch, and perform relaxation methods. You can also apply a warm compress to the painful areas and exercise walking Somewhat slow, easy walking, and jogging are also good for the body. And if the pain is still there, let a specialist examine it.

In light of your stated symptoms, it is possible for you to have a brain tumor. But it is also necessary that you see a neurologist for proper diagnosis and treatment.