@ KseniiaSeaton, don't worry about it. I also applied for N400 during the first week of October and haven't heard anything back. I called the 800 number and was informed that my file was recently transferred to Local Office and i will be scheduled for interview soon. By law, Uscis have to schedule you for interview within 6 months otherwise you can file a lawsuit. I would advice you to call the 800 number and request to be transferred to Level two Officer. They should be able to provide more information regarding you case.