I have occurred a similar issue in the past. For about a week I began to feel extremely depressed and unmotivated. Life felt far more trivial as opposed to meaningful. I felt that there was little to about it. I'm not sure if the depression spell caused by a form of green out or possibly just a combination of various chemical factors.
I found a quote from Bob Marley that summed up my thoughts at the time: "When you smoke the herb, it reveals you to yourself."
- This quote may relate to yourself, if you have unconsciously been blocking out personal issues, smoking will just act as an overdose of reality.