So after a little research I found out why I felt so crappy the next day after taking the ZMA. For some reason I require dreaming in order to feel awake the next day. Not sure why (Note: I believe this to be because I require the idea of a passage of time) but anyways here is what I found:
Serotonin, which elevates moods, is dependent on magnesium. A magnesium-deficient brain is also more susceptible to allergens, foreign substances that can cause symptoms similar to mental illness.
It seems that if you run out of 5-HTP you may want to try out the ZMA to get your before REM nap.