I agree with feathertop, if she has a cold, then she won't want to sleep. Nina always has a rough sleep when she has a cold, hates sleeping on her back. Give it a few days. If she is teething, and it's the top teeth coming through, then they possibly could be giving her some grief as they do hurt the little ones.
Are you giving her anything for her cold, Dimetapp or Demazin?