Oh, honey, I'm so sorry you're going through this!
(((HUGS)))
I agree with the idea of raising your rates and either requiring a set schedule or a flat rate. I charge $30/day for part time and only about $24/day for full-time. For a partial day (up to 4 hours) I charge $20.
How much more do you need to be making each month to make ends meet? Can you take a couple of overnight kids or second shift kids?
Can you apply for any state assistance (food stamps, etc)?