Your room should feel like a place you actually want to be. You do not need a big budget to get there, just a few thoughtful changes.
Start with the light
Overhead lights are harsh. A small lamp in a corner, or string lights along one wall, changes the whole mood of a room instantly.
Add texture
A soft blanket at the end of the bed, a rug, an extra pillow. Rooms feel cozy when there are things you want to touch.
Make one small corner yours
A reading chair, a desk with your favorite things on it, a shelf of books arranged by color. One special spot does more than rearranging everything.
Keep it tidy enough
Not spotless, just tidy enough that you can relax. Five minutes at the end of the day is usually all it takes.