You're most likely to be having blepharitis in your eyes. Grittiness and sandy feeling is most likely due to that. In this condition lid hygiene is of utmost importance. Lids should be daily scrubbed with diluted baby shampoo. You should use a preservative free lubricating eye drop like Refresh Tears. An eye ointment like Tetracaine should be applied at bedtime. Warm compresses are helpful. If this does not help you cn go for an oral doxycycline course for 2 weeks. Also dandruff(if present) should be aggressively treated with medicated shampoo like Nizoral. Thanks and best wishes.
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