I agree with the others, I had this happen to me and thought I could just work through it. Usually by the end of the four hour show I could hardly talk, then the next morning it was back to business as usual, until last July it didnt come back the next morning, my Dr. told me to take off for at least two months and let my vocal chords recover. I would check with a Dr. and probably seek a vocal coach. Oh yeah the water definitly does help. Keep one onstage at all times now. Good luck.