No i don't drink soda or coffee.
I heard it could be because i don't get enough iron in my diet.
Thank you for your comment!
Do you drink diet soda or use artificial sweeteners in your coffee, etc.? Aspartame reduces seratonin production and has been linked to a variety of symptoms like yours including memory loss, mood swings, inability to concentrate, etc.
Check out http://www.mercola.com/article/aspartame/index.htm
Best wishes.