Dry tongue and not even water helps!

So I've had a dry tongue for the past 4 days. I thought I was dehydrated so I kept drinking water but that didn't do anything. I don't even feel thirsty. I've been drinking a lot of water just in case but nothing has changed. I had no bacteria in my mouth either. I don't know what it could be. I have never experienced this before. I also had unprotected sex when I was ovulating so I don't know if this is early pregnancy symptoms ? HELP. Should I worry?