M.S.
In my oppinion its not a good idea to take a step back and by putting her back in diapers or even pull-ups that would be telling her its ok. I (and my daycare) potty trained my daughter when she was 18months. she is still in a pullup at night and has times she wets herself but I just clean her up and put different panties on her, she needs to know that its not right to wear diapers anymore those are for babies and you have a big girl now. Yes its VERY stressfull but stick with it bcuz she knows how to do it and when to do it and she needs consistancy, she seems to be testing things which is what a 2 year old does :) Good luck with everything.