Red skin and white patches on back of head

hi! So foolishly i decided to cut my own hair. I messed up along the way and had to shave it all off. Anyway to my horror ive noticed the back of my head is bright red with white patches. For reference im 22 years old. Anyone know what it could be? (Image attached) Thanks in advance

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If it doesnt itch or irritate then it may be a birthmark. If you can, ask your Mum…she should be able to tell you. If your Mum is adamant that it wasnt there when you were born then do see a doctor or dermatologist. I dont think its anything to worry about.