I have this little red 1 on the top right of the GC icon on my screen and I have no idea why! You open the app and there's nothing telling you what the notification is for. It's not connections, I cleared that...
I have the exact same issue - for like a half a year. Even un- and reinstalling the app completely did not solve it. Also deleting and switching to a new watch did not solve it. GCM is such a mess.