Any needle used for a filler or Botox can cause a bruise since small veins and capillaries are not visible as they underneath the skin and it's just luck that they're not hit more often. On the other hand, botox underneath the eyelid is usually only one needle stick, superficial and this bruise in this photo seems excessive for such treatment. Some people are more prone to bruising if they have genetic problems with clotting, or take medication that can thin the blood such as aspirin (no matter how low a dose), Alleve, Motrin, Ibuprofen, Advil, fish oil, Vitamin E, Gingko, Ginseng, Garlic Tablets, and others. If you had filler, however, such as Juvederm or Restylane and it was injected for the tear trough, then your bruise, although rare for this too, would be more commensurate with such treatment.
I have found that warm compresses rather than ice a few days after treatment helps get rid of bruises quicker than no treatment. Topical vitamin K (we use Auriderm as not all Vitamin K penetrate the skin equally), Anrica montana by mouth, and V-beam laser treatment all can add to a hastening of resolution. Green and yellow concealers exist and neutralize the red/purple color and you may need to try each to see what hides the color better. Special makeup, using a concealer first that makes the purple more of a brown shade, is useful as a base coat and then foundation. Some brands are Physician's Formula, Covermark and Dermablend.