Do you still have a lot of 'pedal'? If so, I would think you should be okay to make it home. MY rear rotors are rusted, too. I thought my calipers may be frozen open, so I replaced both, but now, I'm having trouble bleeding them. My pedal is going almost all the way down, before I have any real brake, and I'm worried I may have a bad master cylinder, instead.
IF you are still stopping okay, then take it easy, leave yourself extra distance, and worry about it back home. But, CHECK YOUR BRAKE FLUID!!!
Good Luck!
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