I applied ED to Northwestern and got rejected, so I decided to apply ED II to another school that I really want to go to. Is this technically allowed? I know I don’t have a committment to Northwestern anymore, but I don’t want it to reflect negatively on me with the other school that I applied ED to another school.
Yes, it’s allowed. You have no commitment to ED school because you were rejected. It won’t reflect negatively, you are not telling the 2nd school about other schools you applied to.
It is perfectly fine to do so. Your rejection at Northwestern means that you have no commitment to that school in any way and are free to apply elsewhere as you wish. Good luck with your ED2 school.