Why arent my antibiotics working?

ive had a sickness now since last wednesday night...since then everythings gotten better. Though on sunday I woke up with my ear feeling like it was plugged and it sometimes hurt. two days later i woke up with pink eye. the doctor said i had an ear infection, and upper respiratory infection, a sinus infection and pink eye and prescribed me with an antibiotic and eye drops. that was tuesday and now it is friday and my eye has gone away almost completely. I have been taking a pill twice a day (eye drops twice a day as well) but my ear is still plugged, and still hurts occasionally. it feels like it hasnt gotten better at all. i still have about 6 more days worth of taking the antibiotic, but Im puzzled as to why the eye would go away yet the ear hasnt even improved. thanks