If you attached the mobo directly to the case without the standoffs, you may want to discretely return the mobo (and possibly the PSU too). It's pretty likely you've damaged the components and, despite the fact that it may work fine now, it could suffer an early death.
Well the case might come with standoffs hard mounted in, I'm not sure on that case, some of the cheap ones do. So that might be why OP didn't use any.
Although, it seems quite easy to discretely return parts to newegg for sure. I discretely dropped my CPU on a granite table, and discretely bent most of the pins back and discretely told them that a shop told me the CPU was bad.. Got an advance RMA for it, and the return was discretely accepted.