In fact, I also think it is a little hard to tell the difference between them. As far as I know, the relationship between pink eye and allergy eyes is just like the relationship between reason and result, for instance, maybe your kid's pink eyes are caused by the allergies, but we can not say all the allergies will cause the pink eyes. If you are not sure about it, you can get the answer from following symptoms cause by pink eyes and allergy eyes. Besides, the symptom of allergic eyes is itchiness. Allergic conjunctivitis will classically manifest as severely itchy eyes, with the itchiness, you can also find your eyes are tearing with little discharge. At the same time, "pink eye" is characterized by mucous, thicker as well, discharge, affecting the eyelashes, especially when feel sense of eye discomfort instead of the primarily itchiness in the morning. Although you can get the answer, you had better go to hospital. Good luck at doctor's.