Just a quick color edit, I didn't move any of your pixels. I combined a few of your colors that were almost identical, you can definitely get more use of your current colors by re-using them. Also dropped the bright white to a gray, it really jumps out and detracts from the piece imo. You may do well to ditch the 100% black, too.
It's not a bad piece! Especially for your first. Considering it is your first though, you may want to start smaller- you could easily fit this much detail in half the room. Then you'd have less overall detail to worry about, which may help you move forward with this piece. Totally your call though, if you feel comfortable adding a lot of detail at this scale, more power to you.
By the by, this forum scales images when clicked, so you should post your work at 1x scale.