It's also okay to not be super far ahead in levels right away (or ever). You have at least a couple months to get into the higher levels. It isn't a race. You have plenty of time. If you're playing a couple times a week you'll be perfectly fine. :s
"We intended the Mastery Pass to provide a scaling reward based on the amount you play. The current track’s rewards are designed to mainly peak at level 80 with the following levels providing a ramp down in value."