Just take it easy, there will be plenty of chicago left when you get here.
Also, other $$$-related thing about living in the dorms is what you eat and how overpriced/mandatory the meal plan is can really change the equation. If it's all fixed price buffet style and you're a 3 chicken breasts for dinner athlete type or you would be eating out or buying prepared foods anyway you can come out way ahead, while vegetablearians who cook a lot might save a bundle living off campus. More something to think about in your later years, but it's something that I really noticed when I left the dorms behind. As Chicago goes it's a pretty great and cheap neighborhood for groceries, you're near trader joes and stanleys.