experiences with overadvancement? LJS/BSSO

i had an overbite before surgery, now 4 days post op and i feel like i have an underbite. surgeon told me before surgery his plan was to move my lower jaw 3-4 mm forward but after he said plans were changed and they moved me 6 mm instead. is my new underbite fixable by orthodontics/could it just be a result of swelling?