Why are the 'whites' of my eyes not so white? they can look a little red/yellow at times, but they're always dull.

Gilbert's?: Whites are not always pure white. If they seem to be a little more yellow from time to time it may be that you have gilbert's syndrome - a common abnormality in which the breakdown products of your red blood cells are retained in your bloodstream and give your eyes a little yellow. This can be more pronounced during times of physiologic stress.