Items suddenly missing.

So I have a Level 85 Paladin. I am playing Holy and Retribution, and I collected items for both (and a couple of items for Protection). When I entered the game this morning, I played as healer in one dungeon and everything was alright, but a couple of minutes ago I entered the game again and wanted to play as DPS, but almost ALL of my Retribution items are missing from my bags! How could this happen? I did NOT sell any of them or anything like that. I had somewhere around 325 item level.

Can anyone help me with this? Thank you!