Laravel carbon createFromFormat增加1年

I´m trying to use carbon for use diffInMinutes, that works great, but before I do this I convert my timestamp in carbon format I do:

$teste= '2014-12-12 15:00:00';

$entrada = Carbon::createFromFormat('Y-m-d H:m:s', $teste);

but when I dd($teste, $entrada):

string '2014-12-12 15:00:00' (length=19)

object(Carbon\Carbon)[340]
  public 'date' => string '2013-12-12 15:00:00' (length=19)
  public 'timezone_type' => int 3
  public 'timezone' => string 'America/Sao_Paulo' (length=17)

anyone knows how fix this??? thx in advance

I don't know if this is the issue but your date format should be

'Y-m-d H:i:s' not 'Y-m-d H:m:s'