I would like to see more shots of the room from different directions. If you could reply to this thread with more pics, that would be fab.

As for creating a warm, inviting room, you can still go with a blue color, just aim for a warm one. I'm assuming you want to head toward the blue range with what you have so far. Correct me if I'm wrong.

Texture is also very important in a bedroom. Think about what textures signify cozy/warm/inviting to you. Incorporate them strategically into bedding, flooring, and window treatments.

I have to say that your bedding and lamp don't speak modern to me. Headboard, yes. Nightstand, I can't see it.

Paint the walls and the ceilings the same color.
I like the wall color in this room (warm gray)


I also like this wall color


Since the room is so small, consider a wall sconce instead of a table lamp. You need all the nightstand footprint room you can get. I like one with an arm because the flexibility could be useful.