Banning you from the museum implicates your due process, equal protection, and First Amendment rights.

Generally speaking, a person banned like this would be unlikely to collect any damages, but may be able to obtain injunctive relief to prevent the museum from enforcing its ban. Of course, it would depend on the reason for the ban and the procedures the museum went through in imposing the ban and permitting you to challenge it.

In your case, though, the ban has already been lifted, so there's probably not much room for any kind of legal action.