Baby making herself sick?!

Ive never been a big fan of the cry it out method but we gave it a try when we were transitioning from bed-sharing to cosleeping and it worked pretty well. Im currently 35w pregnant with my second baby so i make sure to give her as much attention as possible so she doesbt feel like she is being replaced or something. Lately, her sleep pattern has been all over the place! She went to sleep without even finishing her bottle on my bed, i then transferred her into her crib in her own room now. She stayed asleeep for about half hour and then woke up all of a sudden. I was hoping that she would just go right back to sleep so i let her cry it out for a bit. When i noticed that she was just getting more and more upset instead of callming down, i went to go pick her up. But by that point, she had worked herself up to the point that she started full on vomiting before i even got to her.

Is this normal? I know many of you dont agree with the cry it out method but i really dont want to debate that, i just want to know if anyone else's LO is crying to the point that they throw up? P.s i didnt let my daughter cry for more than 15 mins. I just think that she is having such an extreme reaction and i really thought she would be better at self soothing by now.