Caramel is what sugar turns into once you heat it to 161C or higher it's not sweet, it' sugar that's been denatured.
Caramel flavourings can be sweet. It depends on the flavour house.
If you've mixed EM and after a while some crystals are at the bottom of your bottle that's a good thing. It means the EM is about as saturated as it can get. Warm it up a little and the extra heat will dissolve the existing crystals (which will dissolve a lot better once you add it to e-liquid.)