It all depends. Assuming you aren't a substance abuser, your doctor may be willing to write you an emergency rx to have at home in case something like this ever happens.

I get so nervous about the 2 day thing. Pharmacies screw up so often or have some random issue pop up, so I always put my order in early. The thought of going without a benzo if you have constant panic or ptsd, is absolutely terrifying. Being judged by some arrogant pharmacist is the last thing you need in that moment.