Is this normal day 7 after neutered?

Hello - and no, swelling and bruising of the scrotum is not considered 'normal' after castration.  However, it is a common complication of the operation and - if you've ever watched a bruise on your own skin, you may have seen this - it can look worse before it looks better.  However, from here I am unable to palpate the area, to check the wound or to assess for concurrent problems.  For example, some dogs this happens to have a clotting problem and a full examination might help to pick this up.  Therefore, we would reccommend a post op check with your vet.

The other point is that the vet might want to review the patient's pain releif.