There is one thing I do not understand, which is why would I start to feel giddy and my left ear feels block. I wonder if it is because I am lack of some nutrients.

My own analysis of this condition is to think of it as how I would feel if I go without water for days, I would only sense the thirst after sometime. I may have lost a lot of nutrients through the blood lost in surgery and my body is sending signals to me asking for replenishment in reserve. I am starting to include a wider variety of food in my diet.