I completely agree with my colleague on the two possible outcomes.
I normally suggest that my clients check their case numbers online in the online system starting 48 hours after the interview - often, the case will pop up as approved here first (though don't worry if it doesn't - this isn't the most reliable system).
Use this link to get status using your I-130 and I-485 case numbers: https://egov.uscis.gov/cris/Dashboard.do
There are a number of things that could happen after an interview. You could be approved and sent your green card and the officer may have just needed a supervisor to review his work. Another possibility is that you and your spouse could be called in for a second interview to question you further as to whether your marriage is bona fide. If you are called in for a second interview, I strongly suggest you hire an attorney a to accompany you and your spouse and prepare you for the interview.