The weeks in your program are based off of 7 Day periods. These 7 day periods begin when you join the program, not the start date of the program. So, if you join the program and don’t start it for a few days, the counter will start tracking from the day you joined.
If you’re unable to complete your workouts for that week or if you move on to the next week prior to a 7 day period elapsing, you will not see these “completion” markers.
Feel free to work out at your own pace. Do what works best for you and feels good for your body! The number of the workouts in your program per week are what your trainers prescribe for great results. You can always check out all of the workouts you've completed in your recent activity in your profile!