Hello dear ... I would like to know little more info or history of your problems.. It would be great if we can continue our conversation on my private window as here I am restricted to give you few line of treatment..

since your tests are normal, why dont you try changing your lifestyle following lifestyle changes which could help: - Drink lots of water and stay well hydrated at all times of the day(Aim to drink 2.5-3 liters of water everyday) - Be careful with caffeine aim to drink caffeinated drinks such as coffee, tea, cola just 1 or 2 times a day, above 6 such drinks would make you irritable, anxious and will negatively affect your performance - Don't skip meals, Eat healthy, clean and nutritious diet, Don't crash diet - Eat iron rich food, green leafy vegetables and fruits - Adults need upto 8 hours of sleep per night - Destress yourself with methods such as yoga/meditation. - Exercise regularly

There isn't sufficient information to suggest a specific diagnosis. I would advise you to visit a MD general medicine so that you can be evaluated and undergo further investigations such as thyroid profile, vitamin b12, etc to find the underlying cause and have it treated accordingly.