Dragonbub, I don't know if I'm in exactly the same situation as you, but most times my three week old DD will only fall asleep if we're holding her. If I put her down too soon she's awake immediately or in a few minutes.

We found one reason seemed to be because the bed was cold compared to us holding her, so we'd hold her wrapped in her blanket, then when we lay her down it was behind her back and warm, and we draped the rest over her.

The other thing is that she wasn't in a deep enough sleep. Now we wait till she's well and truly out of it before putting her down and almost nothing could wake her lol