Is “everyone went to the dance, but me” a compound sentence?

"Everyone went to the dance, but me," is not a compound sentence.

Explanation:

A compound sentence is--similarly to the sentence in the question--something a comma is present within. The similarities basically end there. A compound sentence is the joining of two separate thoughts with--in general--the first being a complete sentence with a subject, and the second being an incomplete sentence, but having a different subject.

In the above sentence, the first clause is a complete thought that could be on its own,

but the second sentence is incomplete without the first even with a subject and verb.

That's the best explanation I can give on compound sentences.

In your case with the sentence, "Everyone went to the dance, but me," there may be a subject, verb, and complete sentence in...

but even with, "But me." being incomplete, the fact there is no subject nor verb removes the possibility of it being a compound sentence.