Too busy! Lots happening in your room already with the louvre detailing on the bed and the patterned linen. Often less is more, you don't need more decorative elements. Consider a simple mirror or a simple wall sconce. Nothing more!

Save the wall stickers for the nursery.

Dr Retro House Calls

I'd go for a sepia toned picture in a dark frame -- as close as you can match to your bed and cabinets -- get a photo you like ( even a modern one , a personal family pic or a sunset or whatever takes your fancy ) , get it sepia toned and printed around 40x 50cm , have the frame at least 10cm wider ( with matt white card infill ) so it all looks period .

You can even do smaller ones for the other walls .

I know you want something you've made yourself , and I can understand that , but I'd reinforce Dr Retros comment that it could easily detract from the aestethic .