Laymans guess:
1. At least as to initial burden, employer needs to show you quit if they seek to prevail as to UC claim. .
2. In many circles, to not pay timely constitutes a constructive dismissal or similar legal words.
3. If you ramble off about unsatisfactory working conditions it begins to read like you did quit / walk out and I'd NOT go down any such road.
4. If you were required to work extra time for whatever she required you do --and she failed to pay --you may well have a decent claim for wages, and OT if it was that long a day --but thats an unpaid wage claim--a different area of enforcement.
4.1 Your post is very unclear if you were paid $X hr and then to be paid more for longer day and she failed to pay you for longer day or she promised to pay you extra per Hr for a more demanding day due to grandchildren added to list of duties but you never got any such raise. Detail matters a lot!