If there is noticeable resistance in the motor but still works, the copper coils look fine, and there is no odd smells from the motor, just watch it for now as suggested.
If the motor should need to be replaced I would avoid DJI and replace it yourself if you can. DJI customer support is a nightmare and will not cover a pilot error unless you have DJI care on your drone. They will charge you sending/return shipping, the cost of a new motor, and labor costs. In the end you will probably pay over $100 for a new motor.
Replacing the motor involves soldering which it sounds like you may not own an iron, but I would avoid DJI as much as you can.