Dew claws are in the front 2 paws.
My girls both have their dew claws and as long as their trimed properly and your careful when you put clothes on them, it's fine.
They should have 4 claws on each paw in the back. I have no clue why your's has five
Is it like an extra toe or is the fifth claw in the same place as a dew claw would be?