The first few weeks with a baby are tough going - it's never what we expected it to be. Your baby is pretty much following a normal pathway. Babies are often quite "mellow" in the first couple of weeks - maybe getting over the birth, maybe a little jaundiced or having the effects of some drugs their mum took in labour in their system. Just as mum and dad are patting themselves on the back as to what a good sleeper she is, they wake up! And mum and dad get to know what *demand feeding* is - they become VERY demanding. At the moment, just go with the flow - I don't think you need to see problems just yet. Sleep when she sleeps - get a sling like ABA's simplicity sling. In fact - join ABA - it's sort of like an insurance policy against the plethora of unhelpful myths you will face. After a lifetime of being held and cuddled by you (inside you) no baby is going to *love* being put to bed alone and expected to sleep.
Tell me, what have her wet and dirty nappies been like? Colour? Quantity? Have you had her weighed since hospital discharge? How is her weight going?