Greetings! 1. Your description of symptoms is not adequate - bottom of penis - u mean the lower shaft ? or lower part of the glans? 2. Photos may be sent on follow up messaging that may help diagnosis 3. You may be having a fungal infection / intertrigo - due to the heat / friction 4. Sometimes more than one or two visits are required to the dermatologist for adequate relief from the problem. Hope this helps, Warm regards.