Big trouble in application process. Looking for help!

Hello,
I have submitted cmu application as an ED decision. I should have applied College of Engineering and I wrote about mechanical engineering in my supplementary essay. However, a few days ago when I checked my application status, I found the college I was applying to was Mellon College of Science.
I asked my teacher (he took part in my application), and he said he changed college because MCS has higher acceptance rate…
So I’m a little bit confused. Should I contact the school and see if there is any possibility to change the college?

Contact the school. Call the admissions office first thing Monday morning and explain.