As others have said, I agree it's Rand. That's the only way the reaction makes much sense.
Regarding the two uniforms, I think we have to assume that the two uniforms are potentially interchangeable - not unlike what we saw with the TNG/DS9 uniforms for a while.
Regarding Rand's changing rank, we might want to assume that one rank is actually her "correct" rank and others are a mistake. I think it's generally assumed that she was enlisted, but given her position aboard the Excelsior
, I believe I'd like to think she went back to the Academy at some point pre-TSFS thus qualifying her for officer ranks.
It also depends how much time you put bewteen TMP and TWOK, doesn't it?