Eyes bloodshot and blurry vision

Maybe you are just alergic and rub your eyes often. Maybe you work on a computer for extended hours without looking away or blinking. Maybe you are wearing incorrect prescription eyeglasses or none if you should be wearing. Maybe you rub your eyes in your sleep or sleep with your eyes pressed against your pillow. Maybe you have high blood pressure or diabetes. Maybe you have dry eyes and should use moisturising drops. Maybe you're eyes are very sensitive to environments with cigarette smoke or other irritants....
The list goes on and on...