I just filed N400 on 11/6 and check cashed on 11/13. As of today I have not received notice of receipt yet, however I just realized from my friend that total application fee should be $400 (330 + 70), unfortunately I only mailed check with $330 to INS. I called INS offce to understand it will take 30 days to receive the receipt #. What should I do right now? Please advice since I am nervous....