Take it for what it is, you both acted like unprofessional cunts and you got burned.
They should have paid you period and are total cunts for not doing so, but you should have made sure it wasn't gonna be such a sticker shock at the end. I would never do a project without the band at least having a clue about the damages in the end. You should have updated them on price once you got the rough mix done and let them know how much time it was taking.
To put it in perspective, if I hired someone at $60 an hour and he said "ok" and I didn't hear from him in a week and he billed me for a week of work I would be pissed because I had no idea he was gonna need all week to get it done. Everyone has a pretty decent idea of how long things are gonna take within an hour of digging into something. I would have let them know after that hour was up to avoid headache all around.
Honestly I thought your communication was shit as well, if I don't hear from someone in 5-6 days that I am paying I get irritated. Don't take on the work if your not really going to take on the work.
If you couldn't give the project what it deserved then you should have sent them on their way.
Also: I don't know if your short tempered or what, but I would have personally needed at least one more back and forth before losing my cool in communication. Bands are always going to be unprofessional tools, don't stoop to that level until you really need to
.