Your symptoms almost sound like uveitis or iritis–inflammation of the lining of the eye. Often with this, there is pain, redness around the iris (particularly for iritis), sensitivity to light and sometimes blurring of vision. This can be associated with less commone infection (CMV, toxoplasmosis, histoplasmosis, TB, etc) or autoimmune diseases. What goes against this being that, I think, is that the pain and redness did not last days. Usually the treatment is steroids to reduce inflammation and eye drops to dilate the pupil. Other causes of redness in one eye include allergic type reactions–often treated with a different kind of eye drops. It sounds like the ophthalmologist is being careful to check everything out which is what you want to be with eyes–they are very important!