in my opinion we have because we haven't only discovered normal coulors like purple, orange, blue, red etc. we have also discovered various shades of those coulours. but there is a possibility of some colours we haven't yet discovered.
i would say no -cuz we measure distance of galaxies by the red shift within 13 billion light years ,galaxies farther away we cannot see cuz the light never reached us yet -so what spectrum of the red shift are they we do not know