Ok, I will try typing again. My computer gives up on me quite often...I think its time to replace it!
Looking at your picture, it does not look like you have a fungal infection. Below is a link to what a fungal infection looks like. Usually, if there is a fungal infection in the scalp, there are patches of hair loss with it. On your picture there does not appear to be any hairloss.
You have a rash which is very common. It is really not even a rash, more like skin discoloration. We see this more often on men who shave or who have their hair cut very short. In this condition, just as you describe, there is no itching, pain, scaling or any kind of feeling of the rash. It is not cause by a bacteria infection (otherwise you would have pimples), not caused by inflammation (otherwise you would have scaling and itching) and should not be caused by fungus (fungal infections you can feel with your finger, there is an elevation of the skin in the fungus infection, and there is usually itching present).
What I would suggest is that you dont shave for a couple of weeks. Also, you can use Hydrocortisone cream which you used before. I am not sure how often and how long you have used it, but it is recommended to be applied twice daily (small amount). You may find that it is too greasy to apply cream into the scalp so you might talk to your doctor about getting a prescription for a foam or gel.
Also, I will be working with a dermatologist on Wednesday and will ask him for an opinion. If he gives me some other options for you, I will be make sure to get back to you.
Again, my apology for such a long time in answering you.
I hope you find this information helpful. If you need any clarification or have any additional questions, please let me know and I will be glad to assist you further.
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