Hi, I'm new here, my name is Laureano and I'm from Argentina. I've had CFS for 14 years being now 28 years old. I've got many symptoms, but one I've never found information about is the one described in this post title. When I wake up after a night sleep lasting 6, 7 or 8 hours, I don´t experience this symptoms, but when I wake up from a nap I always take from 14:00 to 15:00 hours (when I come back from work), 8 of 10 times I experience this symptoms just after waking up. The symptoms appear even if I still lie in my bed, it isn't necessary to stand up for them to show up; and if doesn't matter if I stand up slowly, first sitting and the standing up. Once I registered 130 beats per minute, when normally I'm 90 beats per minute, and I suppose it should be even lower while sleeping. Anybody has a clue about what this could mean, I would be very grateful to anybody who could answer