And i guess the change in her mood from day to night is so vast!
Absolutley and remember that they don't know the difference between day and night.

Babies usually have an unsettled cycle. Angus was at 10pm for a feed or two and Caleb was from about 3am to 5am (my little morning feral man I called him )
There isn't much you can do to tweak this. Just live by her routine for a bit and sleep during the day when she does.

You could try sleeping her on a firmer surface. I found the opposite in that situation though. A huge nappy blowout resulted in me having to wash the underlay and for the few days it was off the cot Caleb was very restless. When I put it back on he slept better.

If you're comfortable with co sleeping then give that a try. I co slept for the first couple of weeks till DH went back to work.