Hmm ok. Is the cage parallel with the ring? When you look down on the FD cage, it should be in the same "line" as the big ring; not twisted or what not.

If it was shifting correctly before this morning, it has to be something simple. I doubt your limit screw would turn itself.

Please post a picture with the FD in the position that's causing the problem...It's hard to diagnose over teh internets.