I too had the swelling and still have a little. You can use the search funtion on here and find lots of info on massaging your chin. When I do it, I find it just about disappears. Then it will eventually come back. My friendly doctor (NOT) told me to learn to live with it. I told him I was learning to live with a lot and that was the least of my problems.
At first it didn't seem the massaging was helping. But time does wonders. I would not worry. I still sleep proped up on pillows and have a neck pillow I sleep with. At first I used a reading pillow and just about slept sitting up.
It will subside with time and you will learn how to help.
Debbie