What Causes Strained And Red Eyes?

I know I have a cataract beginning in right eye - - within last month or so, if I close vision of left eye; using only right. there is a splotch - - like a paint splotch - - if I have strained eye, it is red, early morning, upon awakening, I see it black - - under normal day - - the splotch is the color of an old bruise - - brownish yellow - dead center of eye - follows eye movement. am seeing eye dr Tuesday to see if thid id progression of the cataract - - just checking to see what else might fall this way