It's really normal lol - you're not doing anything wrong. I'd put her straight in the sling if that helps. Best to avoid overtiredness if you can. It's ok if she only sleeps in there during the day - dont' worry about bad habits, etc, etc. Will all work itself out in time.

The ergo is quite good, but you need to also buy the infant insert at this age. The manduca, beco or olives&applesauce carriers are all very similar, but can be used from newborns (there are different models sometimes, so you might need to confirm this when you're buying).

You may also want to look at a hammock, some mums swear by them.Trish sells them