To my pace me the same thing that cydia remained stuck in "loading packages" and could not add any source.
solve it like this:
-Sign into cydia and not leave it to recharge, you must cancel.
Sign-in sources and check one by one, there must be one or more sources that are giving the error, the error sources can differentiate because when you open them there is nothing inside.
- Edit and delete fonts all fonts when you open there is nothing inside.
-once you deleted all the error sources close cydia, turn off and on the iOS device, open Cidya and you have to load properly and can add new fonts.
Greetings iOS July 2014