I would definitely time her breathing at different times (time for a full minute) and if it is higher than 60, contact your ped about it just to make sure.
When my first DS was a newborn, he was breathing at between 65 and 90 breaths per minute (!) and when we took him to our pediatrician, we were immediately admitted to the hospital. They monitored him for two days, and did all kinds of tests, one of which showed that he had slightly stiff lungs and a reduced lung capacity. The strange thing was that they were not able to figure out why, but he was happy and healthy and getting enough oxygen, so we were released the next day and he was monitored on an outpatient basis for the next 18 months. Every time we came in with him (weekly at first, then monthly and then every three months), his lung capacity had improved, and at about 10 months old, he was breathing completely normally. We've been told to be a bit alert to indications of asthma as he gets older, but nothing showed up on their allergy screens.
I hope this does not worry you, but I did want you to know that if a newborn is breathing very fast (and remember, my little guy sometimes breathed 90 breaths a minute...and 75 while sleeping, so it was very fast), it is something to take seriously. Probably it is absolutely nothing to worry about, but you should have a ped check it out anyway.
How fast is your baby breathing?
One thing you should know is that they were most concerned about his breathing while he was asleep, and for a long time they asked us to count his breaths several times a night while sleeping.