Oh no! Poor Peek a Boo.
I'm glad he has meds and is on the mend. Max was the same way -- no loss of appetite or activity level. With his first ulcer, no squinting or pawing. I don't even recall any extra tears with the first. The only difference was he wanted to be held more in the evening.
Ulcers do not always appear as white or any other color. The eye can appear perfectly normal, although usually the white of the eye and the lids will start to show irritation. The only way I could see Max's is in bright light. Even then they can be masked by tear production, especially if they are shallow. Scratches can be invisible to the naked eye.
The whiteness is potentially scar tissue that is starting to form. This can happen quickly. It can also go away. With one of Max's ulcers, he had some cloudiness and the doctor said he might have some scarring. He healed perfectly, thankfully. No scars. Can still spot a UPS truck or motorcycle a mile away.
I discovered that Max reacts badly to sterile saline eye drops, even the ones that don't have preservatives. I started using tap water again because I figured it goes in his eyes when he has a bath. Haven't had a problem since.
Sending gentle hugs to Peek and wishing him a good follow up exam.