what nuthatch said. I'm what they call perimenopausal (read I'm Almost there!) and the last year has been very interesting to say the least. Right now I haven't had a period in 6 wks, but between Aug and Nov it wasn't unusual for me to have a period every 2 wks. Some heavy, some a week long, some very, Very light, some only 2 days. I also experienced what you're talking about: waking up in the middle of the night and everything is ruined and my legs are a mess. Me who had Never had anything like that before. Depending on your age - this could just be the beginning of the change for you. But as Nuthatch said...it wouldn't hurt to check with your doc if you continue to be concerned.