IS IT NORMAL BABY SLEEPING FOR 12 hours IN 24 hours????

I kept track of my newborns sleep on this app and she’s almost 6 weeks old. Usually her sleep varies from 14.5 hours to 16.5 hours but she only sleep for 12 hours today… she was having a hard time falling asleep for almost 3 hours so I had to drive around a bit with her so she could fall asleep.. but is it normal for her to only sleep 12 hours in 24 hours. I’m a little worried.