Sorry to hear that, Donna. Check the easy things first, soil moisture...
Insert a finger in the soil near the trunk to a depth of two inches and see if the soil feels dry or wet. If dry then it needs more water; they sure like their water during the summer! If wet, it is getting too much water and you need to cut back. Spireas are tolerant of many soils except those that are extremely wet. Make sure that the root ball is getting wet since roots are too young to have grown much yet.
Other possibilities: Are you mulching underneath the
plant? Pot bound roots could be a problem but I think your
plant would have shown symptoms of this after a year or so. Check for the presence of insects on either side of the leaves.
Luis