Immigration Site

My wife and I had our immigration interview not too long ago.
Given that everything is well, how long does it GENERALLY take to reach decision after the interview done? Like... when I check the application status on the USCIS website, it says Im still in the "testing and interview" process, but not yet the "decision"

As for the interview (if youre curious of this info), the officer seemed pretty rude to us and disrespectful, maybe because we are a young couple (19 & 21). He did, however, say that he will do a background check on me and if everything is well, he will approve. He seemed rude the entire time, even as he mentioned about background check and approval. I dont really have anything to hide, except for the fact that he took my spouses parents # and her parents dont know about my immigration status. I did tell the officer that they didnt know that though. He also took our bank statements, apartment lease, auto/renters insurance, phone bills, and some wedding pics (why the heck would he want to keep our wedding pics if he just saw them?). I just wonder what he means by "background check" that hell do on me. The officer didnt stamp my passport or give me anything afterward.

I hope its not the "FBI background check" thing... as I heard the process can be very lengthy

oh and I forgot to add one of the most important thing... the IO also took the I-94 out of my passport and took that, he also took the copy of my visa that I was used when I legally entered into the US initially

The fact that your spouses parents dont know about your immigration status was a red flag to the IO and could even be grounds for denial. How come they dont know? Do your spouses parents know about the marriage?
The IO will probably call the parents to check everything. You might get approved but this might lead to a stokes interview.