Help! Mysterious Brown Skin Patch Around Mouth!

[Caspian]

A week ago, I discovered to my horror that the skin around my mouth was turning brown, as though that area had been tanned. However, it is also sometimes inflamed and itchy and sometimes it's fine. I have had this before in October when I was using protein shakes, and the skin across my whole face started to become extremely dry and flaky as though I had a face mask on, but after a few weeks it went away, and I don't know why. I went to the doctors and she prescribed me Hydrocortisone cream, but I didn't use it because that was already a thin area.

Three months ago I was diagnosed with a mysterious illness called Petechaie, which are little red dots, I went to the hospital and had some blood tests but they couldn't find what it was caused by, so they sent me home and it went away after a few more days.

I am wondering whether all of this is related somehow, I hope someone can help.

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