hitting your face won't be sufficient to move a filler around...just think of the sustained pressure we use to mold the material immediately after it's injected...and within hours it's even more difficult to move...and of course sleeping applies sustained pressure without compromising the filler...bottom line...any mark you have is related to the trauma and not to shifting filler
I have seen this a few times where indentations have resulted from trauma to the area, some people call it traumatic panniculitis. The filler is unlikely to be displaced but swelling can affect the ultimate results. I suggest seeking a dermatologist with experience in filler injections to check you out. Best, Dr. Emer.
How long ago did you have your fillers injected? What you are noticing is probably a result of the trauma from the rock hitting your face. It should get better with time. I doubt that the filler got displaced. If you continue to have concerns then the best thing to do is schedule a follow-up appointment with the person that did your injections. Good luck to you.