Scratches in my Lumia 920 screen

I got my Lumia 920 last Friday and have been very careful with it so far. I don't have a case or screen protector, but it's always in a pocket by itself and I haven't rested it screen down or with anything on top of it. There are already a few minor scratches, one of which runs about a third of the way up the screen. I thought this was supposed to be difficult to scratch. I'm very disappointed with this happening already. Has anyone else had this issue?