HELP! Overworked and underpaid?

Okay, so its not AS drastic as i made the question sound but I recently started babysitting for this lady (today will be my second day) who has younger kids than my norm, both of which are not potty trained. She is also paying me 3$ lesser for an hour than I am accustomed to, yet she has the most work set out for me. She wants me to have a regular schedule with her kids. My parents didn’t want me to go back to her at all, my question is how do I talk to her about my salary? I always feel its such an awkward conversation, which is why I avoided it in the first place when she told me my salary. My current idea is that I babysit today and one other day that I already committed to, but after that I should talk to her about the pay. What do you think? Suggestions from parents who can identify with her side would be helpful too!