Is my cat having trouble keeping warm?

She is an indoor cat, almost exclusively.  i'm trying to be eco-friendly (and cheap) so i keep my heater set at 60 during the day, and 55 when we're sleeping.  Caramel always hangs around by the heating vent or right next to my laptop (where the fan blows out warm air).  i've heard that's a sign your cat isn't warm enough.  60 is warm enough for me, and my other two cats.  but Caramel, she's an older cat.  i don't know how old exactly, because i adopted her from a roommate who moved and couldn't take her.  could it just be that she's old, and she's also kind of small, that she isn't keeping warm?  or could it be some other problem?  are there any other symptoms i should be looking for?  thanks.

Cats  LOVE heat, they descend from desert cats. Older cats seek out extra warmth too for their achy joints and thinner fur. We keep our thermostat at 70 and my cats still seek warm areas. If you can, invest in a "heated pet pad" for your cat. They are a little pricey at 30.00 -50.00 dollars but are well worth it. They last for years and run on a few watts a day, they don't stay 'hot' all the time, just when pressure from your cat is on them. They heat to approx. 102 degrees. The other day I was in a hardware store and saw a 'replacement'  heater pad, without the cover, etc., that's really all you need, lay a folded blanket over it and it would work. It cost 20.00.

That's a good idea, i'll look into it. Thanks!
 

Two of my cats are heat lovers too. I also have quite a few really plush, high-sided kitty beds. I bought them at a cat show. Really puffy sides and deep. They love to curl up in these beds and they stay toasty warm! for your kitty.