Everyone has already made really good suggestions so I really don't have much to more advice to offer; however...
I want you to know that it is OK that you feel frustrated and IT DOES GET BETTER. When I first brought Tucker home I can remember feeling so overwhelmed and tired at times and I definitely questioned if I had made the right choice (we came home several times to poopy pawprints everywhere, too!)...but with time all those feelings of frustration dissipate (well, most of those feelings as he still can be a little bugger sometimes
). YT has been a savior, helping me read up on everything from teething to potty training to ear infections not to mention the positive support the members here provide.
Tucker's almost 6 months old and has been home almost 3 months now and I am so blessed to have him in my life. Give your girl a little more time (she is still exceptionally young!!!) and know that you did make the right decision and all your hard work will pay off BIG TIME in very little time. Good luck and enjoy your baby!