Hi , red eyes are not an indication of cherry eye -if you have a look in my gallery or Lily's thread you will see how the cherries look like .
Maybe Bryn is allergic to something or something might irritated her .
Mine get red eyes after a long and intense play for no reason -i think it is normal ;-)
Sorry not much of a advice here ,but im sure more experienced members will be able to advise you
Hope Bryn feels better soon x