Hi Pat and welcome to GoY, we need a photo to be able to give you any advice. After you planted the Citisus did you keep it well watered also where did you plant, aspect, soil etc. Any shrub that is actually flowering when you plant it needs a lot of care and attention.

Thanks for that I don't think we watered it enough really. But it just looks absolutely lifeless. Should it stay green?

Yes it should stay green. All I can suggest is scraping away a little of the bark with your fingernail if it is green underneath then the shrub is still alive if not then it is probably dead.