I had that same issue a couple weeks back when I was trying to flash a new theme, I ended up in some crazy boot loop of doom similar to what you were in. I tried the battery pull a few times and couldn't get back to the recovery screen I needed. Finally after about the 6th time of doing it dumb luck smiled on me and I was able to get back in and wipe/format and then install from scratch and all was good. I had no backup at the time since I had just gotten the phone a few days ago.
Needless to say I have several backups now.