Assuming the datasource for your RG is a database search, then you just need to add some constraints on the search to return only Appointments that are scheduled within the current week.
You can use :rounded down to week
for this.
So try the following 2 constraints:
Appointment Date ≥ Current date/time: rounded down to Week
Appointment Date < Current date/time: rounded down to Week: Plus (Days) 7