Pug puppy feet should be rounded and face either straight ahead or slightly toed out. It is possible for the foot to be turned in. Pugs are small and she might be fine if the deformity is minor and the foot is not rolled over. If the foot is rolled over, it may cause long term problems depending on how severe it is and whether or not it will straighten as the pup grows.
You should ask your vet about the paw on the next routine visit. Assuming she is still going through her puppy shot series, this should be within 3-4 weeks. There may be corrective measure such as bracing or surgery.
If you have a healthy puppy guarantee and are not too emotionally attached to return the pup, you should talk to your vet sooner than the next visit. If she is to be returned, it is best done as soon as you have a vet certificate.