Take a big deep breath. You didn't p**s anyone off. It's just that when you are down you notice every little thing that is making you feel this way.
Look at it from your new boss's POV. Firstly they are new so they have to get a background knowledge on everything and everyone that they will be concerned with. Why don't you use this as an opportunity to forge good communications with them. Rather than worry about this and make yourself ill ask to speak to them and explain how very important it is right now for you to retain those hours. Think very carefully what you will say in that meeting as you don't want to come across as looking for favours or that you are not up to the job. If it helps write it down before you go in so that you do not miss out anything important. Do you have a member of staff or a union representative who could go in with you? You might want to reserve the latter for future use just in case.
I recently had a meltdown at work and it's over 2yrs since my H left. I quite literally stood up and walked out over something really silly. It was just the straw that broke the camels back. Initially they were really hard on me until I pointed out that in the entire two years I had only taken 3 days off because of my personal situation. We have been going through a merger and my managers have not handled it very well at all. So like you with everything else going on I really struggled. However I managed to talk to my immediate boss in such a way that she withdrew her harshness and actually became empathetic. Based on what I said that day she has looked at the way the merger has been handled again and is now being far more considerate to me. I also know that if i have a problem I can take it to her w/o fear of retribution.
Keep on taking those deep breaths. Things will get easier. I won't lie to you there will also be further times when you think they are getting harder again but the quicker you can learn to detach the easier those time will be to overcome.
Me 43 XH 45 M 2.7.88 Divorce 7.10.09 Kids D20,S17 & D15