H.W.
He sounds like a toddler, T.. Like every toddler I have ever met. They have no concept of privacy and are on you like a shadow. This isn't a discipline issue-- just the reality of living with toddlers. You have to *teach* them things like "Private time! I use the potty by myself. I'll see you in two minutes." and then praise-- 'thank you for waiting'.
Try to find a book on child development-- this is very common.