I haven't been here in a long time, but need some advice and am hoping someone will help

I am worried it's too cold inside for my little yorkie/chi mix baby (Pixel) today! I haven't had the heat on in days and when I left the house it was 72 degrees, BUT I had no idea it wouldn't warm up and the temperature outside is now only 54. I would normally leave the heat on for him! He is inside and has 2 blankets in his little bed and 1 on the floor (in his big pen where he stays when I'm gone). It's on a tile floor, which seems colder. Will he be okay until I get home after work? I'm so worried about him being too cold!! He is only 5.5 pounds. I would run home during lunch, but live 40 minutes from work! Help! Thanks!