My husbands eyes are both really red. He has used Opcon A for the past two days. When he uses it, it feels like sand is in his eye, but then it subsides and the redness goes away for a little while. Today, however, the redness is accompanied by white spots on his iris. He has no drainage from the eye, but they both feel like they are straining really hard and are extremely sensitive to light, even with sunglasses on. Any idea what this may be?