I've been there some years ago. I also had a normal job + an hourly gig in the evenings + studying for a master degree. I'm not exactly sure what changed but I stopped caring about that race of needing to be productive 100% of the time. It's a fallacy, I think at some point I realised I'll be alright even if I lose everything, I just need food and shelter and I should be able to afford that in most scenarios. I think…
And once you come to that realisation, you can start living off some of those savings just to chill out and not be "productive". While in reality that's probably what you need.
Worst case scenario for the OP is probably finding another gig in a few weeks.