White Tongue??

Is this oral thrush? I've been kind of paranoid lately because of it. My tongue appears white right after I wake up but before I go to sleep it's pink. My guess is that I always get dehydrated after I wake up because I never find myself thirsty before I go to sleep and also I have a tendency to sleep with mouth open due to problems I've had as a child where my nose was always blocked (i'm much better now). Of course to have this clean tongue, I have to scrape it everyday and I know that I'm cleaning it because of the white film that leaves the tongue (amount depends on how much I ate). Though I haven't really been happy with the way my tongue looks. It seems to have these weird sesame looking seed white shapes over it (sometimes they appear and sometimes it's hard to see, maybe lighting makes a difference). The coating is thin and only extends until the red bumps of the tongue (I think they're called papillae?). In terms of symptoms, I don't really put mouthwash because my tongue gets very very dry. My tastes haven't changed whatsoever and I don't display any signs of any pain whatsoever and I've been wondering about this for some time now. I wanted an opinion on whether or not my tongue looks normal or not... Any opinions?