What Causes Pressure On Head,loss Of Balance And Fainting Spells?

Hi last week I had fever and cold. It is now cleared. But now i have some strange symptoms. Sometime i feel like i have a little pressure on head. Like someone has put a book on my head. I feel like i am losing balance and fainting. Specially this happen after i work on computer. Doctor checked my bp and it is normal. Now i am told to take nervup tablet. What do u think this could be?