turn on AC.
Even if you don't have the car in auto, it's still trying to get the air to 65 degrees. Air which was at 30ish degrees, so that requires heat.
In my 2011 I've found that if I leave everything in auto, then set the temp to where I want it, the car will pump heat for a bit, then switch to AC and keep things nice and comfy.
or turn the temp below 65