I don't know what to do anymore. My daughter is 5 and a half months old and NOTHING makes her happy. She literally cries all the time. Tummy time cries, back time cries, sitting cries, standing cries, now even being held she is crying. The only thing that makes her happy is being outside and it's way too hot right now to be outside. I just don't know what to do. I don't want her fall behind in sitting and standing and crawling but she doesn't make any effort on doing anything because she is too busy crying. Any tips would be greatly appreciated.