Just want to have a winge lol

My daughter is 21 weeks and won't go to sleep unless I'm holding her (-_-). At night time she falls back to sleep on her own, but actually getting her to go to sleep sometimes is horrible!!! If I just put her down when she's tired she will fuss, chatter, squeal throw her dummy. About 15 minutes I will leave her and then I have to pick her up otherwise she gets over tired and doesn't go to sleep for another hour or so .. When I'm really exhausted at night time I just fall asleep and when I wake up she's asleep but during the day trying to get her to have naps that just doesn't work,