7 weeks 4 days..

My baby sleeps at 3 hour and 2 hour intervals after that during the night. We usually feeds her every 3 - 3.5 hours. So tonight she woke up at her usual 2 hour interval for the 3rd sleep of the night, we wanted to try putting her to sleep without being nursed. Gave her paci (this is how we get her to nap during the day). She did not go to sleep.. after nursing her she was able to fall asleep ..I know she's not hungry because she doesn't spend very long feeding before she falls asleep.

Am I building a bad habit with her nursing to sleep at this age? If so, how to break that?