You absolutely did the right thing. I once trusted an adviser (she’s a successful working professional; she knows everything, right?) and I’m having some serious problems right now because of it. It wasn’t malicious; it’s just that her advice wasn’t right for my particular situation. If I had checked with someone–anyone–else, I would have realized what a mistake I was making.
Trust yourself. You did the right thing.
I think your advisor is a frosty bitch. It is always a good idea to triple-check things when transferring schools. That said, you didn’t have to tell her that you got independent confirmation. Some people get touchy about stuff like that; no sense making enemies when you don’t have to.
Absolutely NOT. I don’t know anybody who’s adviser didn’t at least have SOME bad information, one of which got such bad advise that it cost him another $8,000 because he had to do an additional semester to fulfill requirements his adviser assured him weren’t required.