She's had a huge nap (2-3 hours) and I had to wake her up to feed. Now fast asleep again. This isn't normal, she usually only naps on and off during the day - but she seems OK,no temperature, not dehydrated (and she fed well when i woke her up). I'm a natural worrier so please be nice (not even pfb!) - is this a sign of anything worrying or shall i just let her snooze on?