Concerned about cavities after 45 days

I have only had this mattress 45 days but after less than thirty days I noticed humps in the center of the king mattress as if the stuffing moved out from under me and into the center of the bed. I have a considerable shallow area where I sleep and can even see a shallow spot after the bed is made where my little 40 pound dog sleeps at the foot of the bed. This cannot be good. If the shallow spots and high spots continue to increase the bed will not hold up over time at all. I am concerned enough that I plan to make a trip to Macy's today to discuss it with them. I don't want to roll into a hole each time I go to bed.