Error coin [Risolto]

I believe i have found a mintage error on my coin, in the year, 2002, the second two is too close to the 0 and it has extra metal. How do i know if its an error for sure?

You could start by showing us pictures.

Hello. Yes the extra metal near the 2 could be considered a mint error as it could be caused by die deterioration. That tends to happen often when the mint makes half a billion of the same coin.  It isn't special and won't increase its value. The second 2 being too close to the 0 isn't a mint error.  The 2 can't magically move about the die.

So is it considered an error? 

Yes the extra metal near the 2 could be considered a mint error.

Thanks!