Yes, you can travel domestically within the continental U.S. You only need your passport for identification. But, keep a copy of the USCIS receipt notice in your bag, but don't show it to the people checking for ID. If there are any problems, you can pull out the copy to show you are in status.
Security is normally checking your name and photo against the plane ticket. Don't worry, you should be fine.
Good luck to you.
Nikiki T. Bogle, Esq
Immigration Legal Team
Bogle & Chang, LLC
Phone: (800) 342-1733 ext. 101
National Immigration Lawyers
We handle immigration cases in all 50 states and foreign countries worldwide.