Hang in there! It is really hard work to stay calm and consistent when you are sleep deprived.... jackrose has given some great suggestions to work with. We had similiar issues with DD1 and had some great advice to hang in there with any routine change for at least 3 days before changing tack - I was so desperate for sleep we were all over the place doing something different each time we put her down - no wonder the poor thing couldn't get back to sleep!
Similarly she was having 3 great naps in the day and then not sleeping at night - so we cut the naps back (a very messy transition period) and created a firm night ritual which included a sleeping bag and her comfort blanket (which I had slept with prior so smelt of me)....and we had to readjust each time new teeth/illnesses arose.
I hope you can get some help to have a few catnaps over the next few days and catch up a little as it so difficult to stay together if you are tired. If you don't mind her sleeping with you - and you are sleeping better you could always do that too!
Most people have some periods of sleeping trouble with littlies - it is no reflection on how you are going as a parent and I am convinced some just don't need to sleep in the way we want them too!
Good Luck!