I have gone through your query and understood your concerns. Due to MDMA you will have urinary retention
so that might be the reason you will be dehydrated and drink more water which causes loss of sodium from your body. Watch for 1 day if you still have the symptoms then you need to consult your doctor. Chances of uti are also high but I dont think that the problem right now is uti. Hope this answers your query. Thank you.