Hi there our Daisy had a big pimple like thing that burst after a day or 2 it was like a propper boil our vet said it could have been black berry thawn that had stung her, to dogs it can give a fairly adverse reaction so has your dog been mooching in black berry bushes the other thing she said was it could have been a tick bite but as yours seems more wide spread maybe its an allergic reaction to the pimple and whatever it was that caused it . is the area that is sore dry too ,looking like excema it could be that if its excema and your dogs scratched it with dirty paws it could have infected it causng the spot. a good thing to try although it can be a bit messy is virgin olive oil sparingly massaged into the affected areas its quite soothing on irritated skin and ive used it for years on such things as cradle cap and psoriosis sorry about the spelling lol .im a hairdresser and i can tell you for skin irritation if you want to go down a holistic route while your waiting for vet diagnosis it cant hurt to try ive had clients with new borns who ive told to use it and within a few weeks its done the trick .
