Post inflammatory changes
Hi, thanks for using Healthcaremagic.
I went through your query and understood your concerns. I have gone through your reports attached too.
with your symptoms it could be the trauma from vigorous friction that have been using during sexual intercourse has led to this trauma and the dark colour is nothing else but is purely post inflammatory (after an episode of inflammation) hyperpigmentation
(increase in the pigmentation) which occurs after any kind of trauma. In this case, it was due to the push and pull of the activity.
Your skin seems to be delicate for the force you use during a sexual activity and hence breaks open frequently.
The red irritated area is due to the trauma that you have experienced. It is normal for an area next to a hyperpigmented area to look a little lighter. You don't need to worry about that.
Just be a little gentle next time around, you wouldn't have a problem. There is no need to worry and the dark color will fade away in due course without any sequel. No need for cortisone
application of cortisone cream do alters appearance of lesions and difficult to interpret at times.
I hope I have answered your query. Feel free to ask further related quires.