It doesn't sound like syphilis. A syphilis sore is round and painless, and not a rash.
Has it changed at all in two weeks? Two weeks is a bit long for a herpes outbreak, and it would probably hurt.
Has a doctor seen it? We don't typically look at pics here- we aren't doctors, and even a doctor shouldn't diagnose you based on a picture of a rash. Rashes can be so many things.
I do wonder about folliculitis, though, especially if you shave the area. You should really let a doctor see it if that hasn't happened already. You may need an antibiotic, or antibiotic cream to clear it up.