Diphenhydramine overdose?

Anti histamines like diphenhydramine can make u very drowsy if u arent used to them, and in high doses can cause all the issues u described. Did you take it all at once or several doses over a longer period? In a person who isnt tolerant to anti histamines, that much will definitely make you sick. Normally I would say you will be fine and just wait for it to clear ur system and drink lots of fluids, but if its really been that long and u have slept and are still feeling just as sick, u should at least call ur doctor and see what he thinks. You may need medical attention. At the ER they can put you on an iv and clear it from ur blood, or pump ur stomach. If it doesnt get better then yes u could have permanent damage because ur liver and kidneys are trying to filter it out and obviously cant do it fast enough. Be safe and contact a doctor now