I'm in east Texas, about 150 miles north of Houston, and right now at 7:00 Am it is 14 degrees at my house; the forecast for Houston for tonight (Monday) is 23 degrees and that it will stay below freezing until about 10 AM Tuesday. So I agree that you need to do something. At a minimum, I believe you should dump your waste tanks, drain the fresh tank, drain the water heater and drain your water supply lines. At that point, some blow out the water supply lines and some fill the supply lines with RV antifreeze. I prefer to use RV antifreeze.
There's lots of advice and information in forums... sometimes it is correct. For example, all of my posts are made by a political appointee who got the job as a reward for contributions to my diesel bill.
2011 Jayco 28.5RLS; 2008 Chevy Duramax; Pullrite Superglide Hitch