Flowering shrubs often look tatty with some discoloured leaves shortly after flowering. How long have they been in their current pots? Need a photograph showing the brown areas on the leaves really, there's more than one cause of brown spots, but here's some info on Camellia Leaf Blight - I don't know if it is that without seeing the plant, but you might recognise the description

https://www.rhs.org.uk/advice/profile?PID=558

I would also make sure that you feed regularly. Yellowing of the leaves can be caused by iron and magnesium deficiency. You need to realise that as you are watering regularly, then any feed will quickly be washed away.