Home Goods and Home Sense are my two favorite places to start looking for cute Christmas décor at a reasonable price. They both have a great selection of pillows and blankets for the season to make your room cozier. Home Goods often has great wrapping paper and ornaments as well as little nick-nacks. Home Sense has really cute staple decorations like a Santa mailbox or a cute slay.
Bath and Body works has the best Christmas candles in my opinion. They have candles ranging from your classic Balsam Fur to unique Christmas-time candles that combine the scent of peppermint with balsam and vanilla. Their candles are on the spicier side for about twenty-six dollars, but they are a large size and last a while. They also often have plenty of sales going on throughout the holidays so you can stock up! Also, if you live in a dorm that does not allow candles they have plenty of room sprays and diffusers in the same selection of scents as their candles.
If you are looking for more upscale decorations local Christmas shops/boutiques are great options as well as stores like Anthropology and Pottery Barn. Anthropology is currently selling beautiful ornament sets, but they range from ten dollars for a single one to about seventy for a set. They also have very nice stockings and candles where everything is in a pastel color pallet for the most part. If you are looking for décor on the cheaper end Michaels and Target have some less expensive, but still very nice options for ornaments, stockings, and gift wrap.