No, the cost of attendance doesn’t change based on ED vs RD. However, as others have said, don’t ED if you can’t comfortably afford the cost.
And, if I recall correctly NU’s merit scholarships all have a need component. Does your family have demonstrated financial need?
Also: if your username is your real name you may want to change it to protect your privacy. Here’s how: https://talk.collegeconfidential.com/t/how-do-i-change-my-username/3603345