Does blepharitis really cause a lot of pain all around the eye?

It can. Since the inflammation of the eyelid margin rests on the eye itself, the eye can become very inflamed and painful. Besides treating the cause of the blepharitis, controlling the inflammation is important to reduce the discomfort. Your ophthalmologist should be able to come up with a program to reduce your pain, .
Yes. It can irritate the eye and cause a lot of pain if it disrupts the tear film and causes dry eye.
It can. Severe blepharitis is uncomfortable and can cause eyelid and ocular tenderness and irritation. This discomfort can be referred all around the eye area and can be severe. Try your regular treatments including lid hygiene and drops if prescribed and see your eye doctor if the symptoms worsen or persist.