I made a recipe for Easter Bread. It had to rise for 12 hours. This morning it was a sticky mess. I added more flour and kneaded again. I am allowing to rise again. Have I screwed up my bread by doing this?
It's very possible.
I have some easter breads that are very sticky (eg, a ham & cheese bread), and others that would be a problem if too sticky (eg, ones that you braid)
I'd stop the second proofing as soon as possible, form the loaves, and then let it rise in the shape you're planning on baking it (aka 'bench proofing').
If you overproof before shaping, you might not get the necessary rise when bench proofing, so it ends up being a very dense loaf