Am I able to return a working (non-defective)monitor that I bought in-store a couple of days ago for full retail (Minus any sort of restocking fee) as long as I have the receipt?

You can return it for a full refund. There is no restocking fees on monitors

As long as you're within the return window there shouldn't be an issue

I believe so, I would just call down there first to make sure.

Yes but donot wait. I bought a battery back up and They said I had 2 weeks to reside to jeep it.

Yes

Call the store.