Belinda, I so KWYM! Kynan has been napping for 45mins and then won't go back to sleep even though he's cranky and so tired that he's scratching at his face. Sometimes I have to rock him for an hour or so. Other times getting him up for about half an hour and giving him a feed helps (or just feeding him back to sleep straight away occasionally works). Luckily he is starting to get a little better.

I don't think I have anything to suggest that you probably haven't already tried. I can understand how frustrating it can be though to have a babe who's really tired but won't sleep!