still no working furnace

Since before Christmas our furnace stopped functioning.  The heating repair man came Tuesday said he would be back on Friday.  It's going on Monday, no tech in sight.  We are expecting an arctic blast this week with temps in the single digits.  John has the gas fireplace running 24/7.  We have a heat lamp in the bathroom 24/7 like a lizard lives in there lol.  Portable heaters in other rooms.  This is getting ridiculous. I am not excited to see the gas bill when it comes.  If the dude doesn't repair our furnce by 5pm Monday, my head is going to split open.