What does Jennet mean when she said, "my little economies," and why did she say that?

Jennet is referring to her own thriftiness.... doing or not doing things to save a bit of money.

She was learning also to over yeast the bread and weight the mugs, so that much of what she served was merely air or iron. She stirred who- knowswhat poor wild thing into the stew and called it beef or rabbit. When important-looking guests arrived and Jennet called to Alyce in a loud voice to put clean sheets on the big bed, Alyce knew she was to do no such thing, but the important-looking guests overheard and were comforted by the thought.

Thundering toads,' Jennet would say, 'I am but a poor woman with this wretched inn and a blind man to care for. I am sure God does not begrudge me my little economies.'