How long can a mother take her child out-of-state for without getting into trouble?

Question Details:

I live in NJ and yesterday I took my 17 month-old daughter with me when I came to NY. My husband and I have been having problems for a long time, and I just wanted to be away from him for a while. I told him that I was going over to my sister's house for a while. He locked the door and wouldn't let me and my daughter leave. I called the cops and one of them said that if I stayed more than couple of weeks, it would be kidnapping and I would get into trouble. I don't want to go back yet for so many reasons. Would I get into trouble? Legally, how long can I stay away from him? Since it involves my baby would I be charged with anything? Can my husband call the cops on me and take my baby away? Important Notice