Lemon geranium looking very sad - please help!

My lemon geranium is looking very sad - this is the first one I have had for years - I love them but have never found them in France so was very pleased when I found one at a local garden center. It was lovely and healthy when I bought it. I can't ever recall having problems with them in the UK so I am flummoxed!

Au secours SFN ers !!