Water will still be in the base.
Pull the dishwasher out and tip it backwards this will allow the water to drain out form underneath so you may need a towel for this part.
Once the water hase drained out retry the dishwasher and see how it goes.
If it does it again then there will be a leak in there which you will need to find. But as its only a week old you will be best to get hotpoint in to find and fix the leak.
But try the above first and see how it goes from there.