“I came inside for winter and immediately became a forensic exhibit.”
The round pale lesions on the citrus leaves most strongly suggest a leaf spot problem, with fungal/bacterial leaf spot the leading possibility. Because the plant is indoors in a soil pot and the leaves are otherwise still green, this looks more like a localized leaf-spot issue than a whole-plant nutrition problem. If the spots are dry, tan, and expanding slowly, leaf spot rises further. If they line up where light hits or where water sat on the leaf, injury becomes more likely.
What to do today
Trim off only the worst damaged leaves if they are heavily spotted. Keep the foliage dry, improve airflow, and avoid misting the leaves. Water the soil normally only when the top layer starts to dry. Watch new growth closely, because active spread on fresh leaves would support a leaf-spot disease.
Also possible, but less likely
What would prove it
Check whether the spots are active
Look at new leaves and the edges of the existing spots. If the lesions keep enlarging or new ones appear, a leaf-spot infection is more likely. If the old spots stay stable and no new spots appear, this may have been a one-time stress injury.
Turn this into a recovery case
One photo gives a diagnosis. Tracking proves whether the plant is recovering.
Don’t leave the diagnosis hanging 🌱
Save it now, then use the next photo to confirm if this was the right call.
Create account & save plant 🌱