several people have offered reasonable explanations for what you're describing, assuming you aren't just making the whole thing up to troll this group.
Thicker/stiffer can be accounted for pretty easily by the piloerection caused by MDMA/speed in the pills, and by perspiration. Hair looks darker when it's wet, so perspiration and increased oil production could account for that as well. Your hair also can appear darker and lighter depending on the ambient light wherever you are. Also, people (especially people on drugs) are highly suggestible. "Hey, doesn't her hair look darker?" "Yeah, I guess it does!"
If you still want to rule all that out, and insist on locating some mystical chemical reaction that's working its way from the drug, circulated through your bloodstream, arriving in your scalp, working its way from one end of each strand of dead protein hanging off your head to the other, to turn it darker (but only temporarily-- then disappearing as mysteriously as it came), well, good luck with that.
Thicker/stiffer can be accounted for pretty easily by the piloerection caused by MDMA/speed in the pills, and by perspiration. Hair looks darker when it's wet, so perspiration and increased oil production could account for that as well. Your hair also can appear darker and lighter depending on the ambient light wherever you are. Also, people (especially people on drugs) are highly suggestible. "Hey, doesn't her hair look darker?" "Yeah, I guess it does!"
If you still want to rule all that out, and insist on locating some mystical chemical reaction that's working its way from the drug, circulated through your bloodstream, arriving in your scalp, working its way from one end of each strand of dead protein hanging off your head to the other, to turn it darker (but only temporarily-- then disappearing as mysteriously as it came), well, good luck with that.