I'm from fl moving to ny and i won't be used to cold weather. can you get hypothermia from 3 degree weather if you're not used to it?

No: Wear a coat. Everyone is susceptible to hypothermia without the proper outerwear regardless of where they are from.

Unlikely: Humans are well designed to adapt to environmental changes. You easily sense heat/cold and would know how to alter what you wear or when to go inside. The pain of cold fingers/body doesn't sneak up on you. In some conditions, like if you were so intoxicated to the point you were unaware of these body senses, it might be a problem if you were outside in the cold.