You have too many spells. Might be Alzheimer's thievery. I'm guessing it didn't restore a spell after death. You learnt a bunch of new spells, went into combat, and then the Alzheimer condition ended and your spell was brought back. Only a guess though, I'll have a look after work.
You can fix this using the renpy console. Type in: len(h.skills) - this will give you the number of spells you currently have. If it's over 8, that's your issue. Simply remove one with: h.skills.pop()
I am allowed to start combat now, but I still can't fight properly; After killing a flame spirit summoned by Asa, it stays on the field, turns blue, and is automatically targeted when I try to attack; it also has a message about not being able to find a corpse?