Go to Settings/Preferences and set Learn ahead limit to 0. That setting moves your cards forward if none are left. The default is 20 mins and that’s why you were seeing them before that time has elapsed. Seedocs.ankiweb.net.
I agree with you it’s confusing. It has a < sign there to signify learn ahead limit but as a new user I always thought it just meant less than x mins (but still higher than x-1 mins).
Yes, for Review cards (cards that have been introduced and studied before today), it is normal to only see them once per day when you get them correct. Studying - Anki Manual