First you have to consult a Dermatologist for this infection to assure that it is fungal infection only and nothing else. Stop using betadine. It will further irritate your skin. Instead you can use dusting powder. Depending on the extent of lesions treatment will vary and if at all it is fungal infection you have to continue the antifungal treatment for at least 6 weeks.
Next Steps
Consult a Dermatologist
Health Tips
Keep your clothes, bed linens, towel and soap seperate. Avoid sweating as much as possible.