I called the Northwest Florida Blood Center and they still maintain that my blood type is A+. The woman I spoke with said they type-check everyone's blood when they donate, so that means they've type-checked my blood type three times (yes, I'm a horrible person for only donating three times) and confirmed that I am A+.
I left a message with my midwife to see if I can re-typed with her to confirm her results. Her records say I'm A-; the Blood Center says I'm A+. I've done some research on the Rhogam shot and I'm not too impressed with the potential side effects or the lack of studies on the effects of Rhogam on a fetus, so I'm praying that my midwife's office's records are wrong. If they're wrong (and I am, in fact, A+), I don't have to worry about the whole Rhogam thing.
And besides, I've really, really liked saying that I'm "A plus". I'd hate to give that up.