I'm two weeks out and most of the day I feel weak and tired? I'm drinking water and Gatorade.

It is normal to still feel tired two weeks after surgery.   A lot of these tiredness is due to the anesthesia.  It takes 4 to 6 weeks to feel "normal".  Continue hydrating your self well.  Take your multi vitamins and protein supplements.  

The most common cause of being tired and weak is not getting in enough fluid and PROTEIN.  You say you are drinking water and Gatorade.  Gatorade is just sugar, water, and a little salt.  There is no protein in it.  You really need to start getting in some protein.I would humbly disagree with Dr. Beltre regarding anesthesia as a cause of tiredness.  People have general anesthesia all the time and are back doing normal things within a few days.  It is highly unlikely that the anesthesia is the cause of your problem.  PROTEIN and FLUIDS!