Foreign material such as Artefill may be causing some of the swelling and this has a small capacity to subside as long as your body is rejecting the current filler.
The answer to your question depends on the duration of time since your injection. Some amount of swelling of the lower eyelids following augmentation of the cheeks may be normal. The prescribed Prednisone, elevation of your head of bed and application of compresses may help. Review of your photographs, especially if your injections have been performed several weeks ago, would be useful.