I am a little confused S. ~ did you first paint and redecorate her room and now she won't sleep in it? Or did she stop sleeping in it so you redecorated her room to try to get her to want to again? Either way, at this point her room smells like paint and she probably doesn't like the smell. Truly, I wouldn't LET her sleep in it until you have gotten the paint fumes out, as they are toxic and carcinogenic.
Getting rid of the paint toxins is easy:
Cut in half 3 large yellow onions. Set each on a plate around the room and leave out for three days. At the end of three days both the onion smell and the paint fumes will be gone. Throw away the onions (do not compost and do not touch with your hands) as they will have absorbed all of the toxins from the paint.
Getting her to sleep in her room again is easy too:
Get out a lengthy chapter book ~ Little Bear, Winnie the Pooh, Francis ~ and climb into her bed with her and read out loud softly and slowly. Most three year old's won't last through an entire chapter, but they will lie still and listen because these stories are so interesting.
If at the end of the chapter she is still awake, sing her a lullaby or two with the lights out - still cuddling in bed with her. She'll fall asleep. Then you can slip out and go on with your evening.
Most children will sleep soundly once they are in a deep sleep regardless of where they are. Once you get this routine down, your daughter will equate her room with stories, songs and a loving bedtime cuddle session with mom or dad. Who wouldn't want that?
Good luck ~ A.