What MrsDuck said, plus dogs DEFINITELY feel off their owner's emotions, so the calmer you are, the calmer they will be.
If your dog is crate trained (which I advocate for all dogs), you can do what my DM did for her Wheaten who was psychotic when it came to fireworks: wear her out during the day, give her the vet prescribed pills, move her crate into the walk in closet in the bedroom, put dog in crate and drape crate with heavy (noise deadening) moving blankets. After doing this a few times, the dog was thrilled to go to it's "cave" and take a nap! (Obviously she checked on her and didn't just lock her in there and close the door...)
And don't assume that "the country" will be quieter, we live in the middle of nowhere, and idiots will be shooting off fireworks all weekend long from their private properties, not just on the 4th. Makes me crazy....
Terri