The red stuff looks a little like staph to me. I'd take her to a vet to confirm. Suspected staph warrants a vet visit because antibiotic-resistant staph (the dog version of MRSA, called MRSP) is on the rise...and it can be zoonotic.
If your vet confirms that it's staph, I would ask if you can try treating it topically to avoid oral antibiotics -- abx resistance is such a profound worry now that it's very much in your dog's (and your family's) interest to try the topical route. Bathing with antimicrobial veterinary shampoo at least once a week will knock it out without oral meds if you catch it quickly -- I generally look for one containing chlorhexidene and follow the bottle directions EXACTLY (keeping it away from the head, leaving it on for the indicated time, etc.). You might need to keep up the weekly baths for a few weeks. You can either buy it from your vet, or online (Amazon, etc.), and there's also a foam that may be useful in lieu of shampoo.
FWIW, even though topical treatments for staph are a little bit of a chore, they save a lot of money in the long run when you catch it early.
Last edited by Magwart; 09-16-2019 at 07:15 PM.