Upvote:9
You should definitely consider an appeal, not to salvage this trip (there is not enough time) but to avoid having an annulment on your record (in Schengen terminology, an annulment implies fraud and is definitely worse than a revocation or a mere refusal).
It is however very difficult to lodge a successful appeal and not something you can hope to do yourself. You will need to instruct an Italian attorney for that, in particular one with a practice in immigration law if you can locate one from where you currently are.