Hello,
Thanks for your query at DoctorSpring.com. I can understand your concern.
From the pictures, it does seem to be an allergic contact dermatitis. However, there also seems to be a fungal component in it.
I would recommend that you apply clotrimazole cream over it twice a day for three days and see if there is any improvement, if it improves then you can continue it or switch back to the cortisone cream that the doctor has advised. Once you meet the doctor, you will get a prescription for a stronger strength cream.
Hope I have answered your queries. Please feel free to discuss further.
Take care