Hi E.,
This may not be what you want to hear, but it sounds like your little girl is dropping her morning nap. Kids love to keep us on our toes and change their routines without letting us know, so we just have to go with the flow.
If she's getting 11-12 hours of sleep every night, she may not need the early morning nap anymore. I suggest trying to push back her morning nap to right after her breakfast at 10 a.m. If she takes a nap, then you can slightly push back her afternoon nap to accommodate the later morning nap. Or, if she's like my niece, she may only need one nap a day that runs right over lunchtime. My niece, who turns two next month, takes just one nap a day from 11 a.m. - 2 p.m. and has done this since she was about eight months old. She goes to bed at 7:30 p.m. and wakes around 7 a.m. My brother and sister-in-law give her breakfast when she wakes up, a small snack around 9 a.m., lunch just before she goes down for her nap, a lighter second lunch when she wakes up, and then dinner around 5:30 p.m. It works for her, and that's okay by them.
Just keep trying out different times and see what works for your daughter. It may also be her teeth are bugging her and that's why she's having the schedule change. But after reading about what happened today and the past few days, my hunch is she's dropping the morning nap. Think about it positively - your schedule opens up SO much more when your kiddo only takes one nap a day! I loved it when my son dropped his morning nap. It meant we could run errands, go to story time at the library, play at the park and I wouldn't have to worry about him missing a nap. I could be at home for several hours in the afternoon and get a ton of things done because he was napping in 2-3 hour stretches, rather than just two naps at 40 minutes to an hour. It was glorious.
Don't beat yourself up too much. Kids are unpredictable, but we love them anyway. Good luck!