We just got back from walking Jesse & Jake and noticed both dogs had raw spots on their pads. They just go shaved yesterday and I'm not sure if they nicked the pads or if it's from just being roughed...
Since they had been to a groomer the day before, I'd think they might have had the hair between their pads trimmed with the clippers and be slightly scratched by that. Were they licking their feet? It sounds like the problem is quickly resolving so that's great.