These details in the painting support the conclusion that the mood of the painting is gloomy and reflective because the subject's face appears to be sad and worried, and his body language, which is him resting his head on his hand shows distress. The use of colors create a sad tone.
I think they adopted Corinthian order, for this type of orders can be seen on many cathedrals around Europe including those in France, Malta (Valletta), etc.
