My 16 month old is giving me the cold shoulder bigtime......?

Just had my 2nd baby a week ago and since then my 16 month old is giving me attitude. She goes to my husband, which is her dad but wont come to me. I am a stay at home mom so all my time is pretty much with her, the newborn sleeps all day. But not sure what is going on with her, last night she woke up crying in the middle of the night and when I went to get her, she didn't want to come to me at all. What should I do? I'm getting upset over this. Also she has been waking up at night crying hysterically, could this also be because of the newborn?