You are not balding. Dont listen to him. Nice haircut. The shorter, the better to diagnose and the easier to care. However, the only one able to diagnose and give you treatment is a dermatologist. You are no longer a child hairline starts to mature at 20s.
And please remember about your psoriasis, it is probably your skin is not able to take some treatments. I would bet minoxidil is bad to a psoriasis skin and finasteride is not for you yet because of your age and because you are not balding.
I would go to a dermatologist and tell your worries, nevertheless you look nice. Try alternative and hygienic-dietary treatments meanwhile and wait for a dermatologist's opinion about starting a more agressive treatment.
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