Workflow firing twice after migration

So after migrating to 2013, a workflow was firing twice! It was driving me bananas. So I re-created the workflow entirely and stopped the old one from firing.

But people were still getting emails twice. It was strange. But in order to get rid of this, I went into the Library menu and went to "Workflow Settings" and from there, I could see several instances of the workflows between migrating and the 2 that I had setup. So you can remove them from in there easily by clicking on the remove link!

Sorted :)