I took ecstasy ("molly"/pure mdma) last night, and the next morning i have one droopy eyelid. what could cause it?

Sympathatomimetic: Sympathetic nervous system innervates the levator palpabrie superioris muscle, which elevates the eyelids. Ecstasy is methylenedioxymethamphetamine and it stimulates the sympathatic nervous system (sns) but it can also cause neurotoxicity of the sns, resulting in damage of the sns. Since, sns elevates the eyelid muscle, it's damage will result in drooping of the eyelid.