Blowing whistle...team losing advantage?

[referee1225]

I have actually had this play happen in a college camp I was attending and here is what I did. I got in between B2 and A2 waited until A1 finished layup blew my whistle and called the basket good gave B2 an intentional and sent A2 to the line for 2 shots and ball at Point of interuption. After game clinicin told me I got the call right.