Go to a local tech store or failmart, target, or w/e, with 15 dollars. Buy a pay as you go phone.
If it gets wet, crushed, lost, stolen, abducted by aliens, or becomes sentient you're only out 15 bucks. Stash it in a zip lock anywhere along with twenty bucks for a taxi/food/tire/lady of the night.

Give the number to family only, in case there's an emergency while you're out.