What happened to my good sleeper?

My daughter is just about to turn 6 months old and has always been a pretty good sleeper. Since about a month old she’s been waking up no more than 2 times a night (most of the time only once) and goes back to sleep with either a bottle or just soothing her (or replacing her pacifier).

Since Thursday she has been hard to put down in her crib- she’ll fall asleep in my arms, but once she gets in the crib she’ll roll over and scream.

Before she would fuss a little, but would generally go back to sleep, now she screams.

We are lucky if she sleeps more than 3 hours in one go, and when she wakes it’ll take about an hour and 5 or 6 tries to get her to stay asleep in the crib.

I don’t remember This with my son, but that was over 7 years ago.

Is it teething? Is it just growth thing?

Will I ever get a decent nights sleep again?

(I get up with her, because my husband gets frustrated after about 15 minutes , though we both work).