Well first off, you're fortunate to have a full head of hair and no balding. Would you consider getting a hair consultation and possibly cutting it to a style....but not super short. We own a salon/spa, so I know a fair amount about hair care. Regarding the dandruff - you could try Nizorel shampoo but use it 3 times a week only. I saw a natural remedy on the Dr. OZ show - mix a 1/4 cup Apple Cider vinegar with 1/4 cp water in a spray bottle. I'll leave the link that explains the instructions.

Use a good quality shampoo. I don't recommend chemical straighteners - they're very harsh but there is a Keratin treatment. Not sure if you like the totally straight look. There are products for wavy hair and ask a salon about those. Be open to a new style, because this could make you look very good and you could always grow it again. Sometimes we get stuck in styles that aren't the best for us. Dove has some very good products to control frizz and you could ask the beauty adviser at drug stores to help you. Here's the link and hope my suggestions help.

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