DD is 4 months old and sleeps fairly well usually at nights. However over the last few days she has been 1/2 waking up crying about every 20mins after we put her to bed. She seems to be still asleep but with a really sad cry. Sometimes it stops before we get to her, sometimes we pick her up and it stops and she goes back to sleep on my my shoulder. I then put her down and it starts again in another few minutes. The last couple of nights it has finally stopped after a couple of hours and she has slept ok for the rest of the night (one night feed as ususal). Any ideas? She really doesn't seem to completly wake up but is just so sad.
Don't think she can need food at that point - feeding her is the last thing we do before putting her down and she crys about 10mins later. When she stops waking and stays asleep she lasts for up to 7 hours before waking properly for food and doesn't cry at all at that point - so wakes up in a totally different way, wriggles and squeaks until I pick her up but no crying.