I know as type1 I suffer from dawn phenomenon , where my liver gives me a surge of glycogen to give me energy after I wake, I hear it’s from prehistoric times when we were out killing things to eat so needed energy I think that’s a load of tosh but there you are . I’m assuming thats what’s happening to you, it’s also foot on floor effect , because it happens as you get out of bed , I suppose it’s your body giving you a boost to start your day, a smart cookie this body of ours.