Wooo, 85 degrees is a bit too warm I think. I believe the target temps are more like 80-83 F
The heat pad will probably be fine if the tempts look ok... you might want to have it on a rheostat (dimmerswitch + extension cord, can find them for a little over $10 at most any goodsized hardware store)
Good luck with those eggs! Do you have an idea of what you will do with the hatchlings? Often nearby reptile stores are happy to buy hatchlings from small breeders