Eye accidentally got head and shoulders dandruf shampoo in my eye? is it dangerous? i feel slight pain, itchiness, and puffiness.

Rinse out!: Just rinse the eye out with preferably saline, but may do so with water. The irritation will go away in a few hours, if not, then see your ophthalmologist.

No: It probably will sting a little but flush your eyes with water and the combined effect of your natural tear outflow will quickly remove it and stop the stinging. Not a problem.