As I said in a different thread:
I've found that smoking pot when coming down from E is absolutely the worst thing you can do.
Sure, you feel great after the bud hits you, but then 15 minutes later you can/will get shaky, restless, and very anxious. My theory is that in your body's state of (extreme) serotonin depletion, the otherwise almost harmless drug marijuana becomes a catalyst, acting on the serotonin system, and in that state it tilts it just that much more and the even LOWER serotonin creates a mild serotonin syndrome where you are anxious and restless.
If you take some clean beans (no caffeine, ephedrine or meth), and do not smoke pot afterwords, you will be able to sleep very shortly thereafter (the most important part of short and long term E recovery, and the retention of the "magic" that is lost so quickly in many users)
But smoke that lovely pot and reap the whirlwind of a long, anxious, restless night. And forget about eating (well) the next day. And the brain damage, oh, the brain damage.
And this isn't just me, other people I've taken it with as well.
And BTW I have nothing against weed. Its great.