It's probably 99% you have a pullet, but I've experienced ambiguous markings on auto sex chicks, and a cockerel can look just like a pullet with all of the markings of a pullet but grow up to be a rooster.
This happened with Cream Legbar chicks, another auto sex breed, I ordered from MyPetChicken about five years ago. The rooster that grew up from a chick with vivid pullet markings mated an EE hen and she produced an egg that hatched into a chick with vivid pullet markings. That chick is now my four-year old second rooster.
Think positively. You have a very excellent chance of actually having your chick grow up to be a hen. Maybe she'll even have spurs. Bonus!