Yeah! I also get confused at the beginning. You have to remember that the flashback is about Sirius' death (and Dumbledore's ring)

Narcissa and Bellatrix scene is outside Harry's POV. I do think it's the first time. After all even the previous Voldemort scenes were from the nightmares and still in Harry's POV. It's quite a change, but I guess that JKR couldn't help it. We need to start suspecting Snape and better introducing Narcissa.