I took him to the vet and it was an eye infection. We were given eye drops for 4 days, didn't think they were working but on the 4th and final day of the drops his eye was back to normal and has been normal since. it was almost like something was "popping out" in the lower corner of his eye because it would come and go. It looked normal and then this irritated looking round thing would be in the corner and his eye ball looked like it was pushed to the side. It was strange but all is great now. Thank you.