My keyboard turned german.

My semicolon is ö

My Y is Z and vise versa

Left bracket is ü

Apostraphe is ä

and shift + any number is all messed up.

I possibly just clicked two buttons at the same time or whatever and firefox makes the switch, because it does not do this outside of firefox textfields...

Any help?

ßßßßßßßßßßßßßßßßßßßßßßßßßßßßßßßßßßßßßßßßßßßßßßßßßßßßßßßßßßß

Try clicking the same two buttons again, but if you don't remember. Well I can't really help here mate. Sorry.

Quote from James Moer

Try clicking the same two buttons again, but if you don't remember. Well I can't really help here mate. Sorry.

That is the problem. I do not know what two buttons they were, otherwise I would have tried that already.

Go to set-up and change your keyboard language back to English.

Where would I find set up? There is nothing with such a name in the above toolbar.

I think you have to go here:

Tools>Options>Advanced>Languages at the bottom>Choose...