Quizzywig all mine are up and about still and very active (although not today as it's pouring with rain and a bit cold) What kind is it? I have a Horsefields, two Marginated and a Hermans. All very different characters and active at different parts of the day but as I said, still very avtive and eating well.
Maybe try giving him a warm bath then offering some of his favourite food - I give mine cucumber when it's very, very hot to keep them hydrated and they have a shallow bath in their enclosure as well.