You are definitely NOT a bad Mom for letting her cry it out! I have done the same thing with my son from the time he was 3 months old (he is now 8 months old.) And even now, if we have a lot going on, or go somewhere for a weekend, when we get back home, he will sometimes cry more when it is time to go to bed. If everything else is fine (she's fed and changed, etc.) then I think it is fine just to let her cry it out and she will get back into the routine. If she is really cranky, maybe she is starting to teethe? I'm not sure if she already has any teeth, but when my son started, he was just crying uncontrollably. I could feel his gums getting swollen and that is how I knew his teeth were coming in. On those nights, I would give him Orajel when I laid him down to sleep. He would still cry, but he would be able to calm himself down to go to sleep. Also, on the nights where he was just crying really hard (not related to his teething), if it lasted longer than usual, I would go in and rub his back and that would sometimes calm him enough to fall asleep. But I was cautious with doing that because I didn't want him to think that every time he cried I would be there, it was only if he was completely out of sorts. Good luck and honestly, don't feel bad for letting her cry it out. She is learning how to soothe herself and learning that night time is for sleeping! Good luck!