Thank you for the reply and for pointing out that Charlie may be a Grey's tree frog. I have just google this species and this is infact what Charlie is. I saw a picture highlighting the yellow on the legs, I noticed this on Charlie whilst bringing her home today. Looks like I may have some more research to do, oh and to have a word with the pet shop.

Your frog looks very cute, I love the green colour. But I'll love Charlie all the same. x