Don't beat yourself up LB - surely that's what our savings are for! I lost pretty much all of mine during covid and whilst I'm scraped a bit back since I'm still nowhere near any sort of decent amount and I'm sure not many of us are sitting on some massive pile of cash.
Have you checked whether there's any financial support you might be entitled to? Even self employed people can get some benefits and if you have long term health problems there might be other stuff too?
Do you actually want to work more than you do? I was going through the last few years spreadsheets a few weeks ago and I noticed that regardless of how busy or quiet it feels I've earned almost exactly the same amount (within £1000) every year for years, and this tells me that I have a cut off for how much I can do no matter what.