Sleeping issue in new born. Be checked?

Hello My new born (11 days old) is not sleeping continuous 5-6 hrs( random time in days) in day. In these hours she is expecting me to feed for sleeping. Even after feed , she is not sleeping. Checked with pediatrician yesterday and he said baby is doing good.  Consulted lactation expert also and no issues with feeding and enough milk secretion. Based on their comments tried side lieing position also to make her sleep but once unlatched she is crying and not ready to latch( opens her mouth and shakes her head even though my nipples are inside her mouth). Is there any underlying cause for this that need to be checked? And how to change this( normal term baby by C section, no issues in baby while delivery )