That would be hard to tell. Could've just been condensation, or there actually may be a leak. Take off the inside cover and see if you can see where the water is coming from. If you can't tell, then remove the outside AC cover and look to see if you can see anything there(probably not). You may even take a water hose and try to make it leak some. My guess is though that it is condensation on the inside of the unit that is mixing with the dust from the filter and giving you the colored water. But I would sure investigate it heavily.
2012 Sandpiper 365SAQ weighing @ 15k, Onan, 2nd air, slide toppers, TST
2013 F350 6.7L Lariat 4x4 CC DRW,Viair 1007, Ride-Rites, Edge CTS, B&W
2001 Chevy 3500CC DRW 4x4, 8.1L, 4.10 gears w/ Detroit TrueTrac
2001 Ford Excursion Limited 4x4 7.3L,V/B Spring Mod, ProComps, Hellwig Swaybar, & other 'Necessities'