Hi! It would help to see the whole Orchid to determine its status. I wouldn't worry about it shedding an older leaf, as long as the plant shows new growth and looks otherwise fine.
About that spot - Orchids do have "blemishes", perhaps there was a drop of water on the leaf and a spot of sun acted like a magnifying glass? Perhaps it is kept too wet? Again, it helps to see the whole plant.
Perhaps we see you on the Orchid forum, where we have tons of information and a special thread dedicated to Phalaenopsis.
The thread "🗣 Starting out with Phals/Supermarket Orchids 🛎 ✍️" in
Orchids forum
Bill, we overlapped!🙂
