As a mother of four, I completely understand how busy you are. If you could take her out in a stroller and maybe go walking in the evenings or on weekends. That's how I got started back on track. Make that time for yourself, you deserve it!
It's okay if the house is not spotless or if there are a few dishes in the sink. Your health and well being is what's important, too. If you're not taking care of yourself, then you can't take care of that precious little girl.
Best of luck!