When you're dumped into worst pony's body, just prior to the date of said pony's banishment, and no one believes you, what options do you have? Well, the answer's obvious: Do your best to not flip your shit, and try to survive the most hostile place on Equis, the Everfree Forest, long enough to reach a city.
Oh, and try not to get roped into the pony Mafia once you get there.

That doesn't usually end well.