Calm down. Just wait for the inspector and follow his instruction, you can show him all the evidence you have and try to convince him.
It is his job to make sure everyone in town is following the code, so don't act like you are a victim. Be nice (offer water and cookie when he comes in) and confident (show him the engineer's calculation and drawings) so he believe you just don't know about construction, not intentionally ignore the law.
Good luck