It is the middle of winter in Australia right now, and we don't have central heating. Our pup (14-month very short hair GSD x Malinois) sleeps in a crate indoors, and the lowest may be 50F (10C). For us, this is very cold, and we have quilt and electric blanket. Pup has blankets, but she sleeps on top and not under it. Is this too cold? shall we arrange heater? How do we tell if she is cold?