I had sores on my inner thighs and genitals, i had a tooth pulled and got ammoxacillin, it went away, but back is this a std?

Maybe: Sounds like a bacterial condition if Amoxicillin relieved it temporarily. Visit an md for diagnosis and treatment asap.

STD: Without seeing and examining these it is impossible to say for sure, but sounds like you may have had a herpetic eruption which cleared spontaneously at the same time you happened to be taking amoxicillin, and that it is now recurrent. You must have this examined by a knowledgeable professional to know what they really are.