3 weeks isn't forever. Relax. Or, if you really want to sleep at night ... take all your papers to an immigration attorney.
The September 29th date isn't a big deal, you can make an InfoPass appointment and get an extension.
PS Yes, being 'light' on your paperwork is probably giving good reason for them to be delaying their decision.
PROFESSOR OF IMMIGRATION LAW for over 10 years -- firstname.lastname@example.org -- www.capriotti.com -- This blog posting is offered for informational purposes only. It does not constitute an attorney-client relationship. Also, keep in mind that this is an INTERNET BLOG. You should not rely on anything you read here to make decisions which impact on your life. Meet with an attorney, via Skype, or in person, to obtain competent personal and professional guidance.
You might consider hiring an immigration attorney. It would have been better if you had hired an attorney before you submitted the I-751 Petition. At this point, you might want to work with a lawyer to see what, if anything, might be done to help your case. Based on your information, it's not clear what USCIS is doing, but 3 weeks is not a very long time from the date of the interview.
(734) 369-3131. This communication does not establish and attorney-client relationship with the Law Office of Michael Carlin PLLC or any individual member of the office. Confidential information should not be sent through this form.