Tossing shoes is something most owners should expect occasionally. Some horses pull shoes and don't notice (like mine, thank heaven XD) and others find it extreamly difficult to cope without a shoe.
When your farrier reshoes the horse, walk her round and make sure she isn't lame while the farrier is still there- the farrier is the man who will be able to do something if your mare is still lame. She will probably be absoloutly fine after the reshoe so there is no reason not to carry on working her normally.
If Alli pulls a shoe I can't usually get a farrier out within 3 days so I have to work her just lightly on the lunge to keep her ticking over. If I managed to get my farrier within 2 days I would probably just rest her for those days to keep the foot as damage free as possible so it isn't weakend for the next shoe.
We lose ourselves in the things we love, we find ourselves there too ~Kristen Martz