Ringworm

I think my dog has ringworm. I has a circular red near his armpit, with black/brown little spots near hair shaft.  ThereAnd it's been there for two weeks now. A couple of days ago I bought some athlete foot cream and I'm applying it twice a day.  First question. What other thing could it be that would cause round red spot? I wash the black/brown spots off but it came back. 2nd question, how long will it take before it goes away? 3rd how long can I wait before taking him to vet? I'm delaying til I get some money maybe after Christmas.

[Dr. Carol Osborne, DVM]

Perhaps allergies and or fleas are this issue your dog is experiencing. Your vet can diagnose and treat this. Ringworm is common in puppies and usually causes circular non itchy scaling lesions on the face and head that are contagious to humans. This does not sound like ringworm to me.
Dr Carol Osborne, DVM