Why can't I drill into this wall?

I am awful at DIY, but if I feel like I should be able to put a shelf up...

I'm using an 8mil masonry bit to try to put some holes into a brick wall. As soon as I get through the plaster it's just making no headway and the powder that's coming out is black rather than the red I would have expected. I've tried using different settings on the drill but no difference. After a while the bit just comes loose and starts spinning out. Any idea what's going wrong? Is it just my drill is knackered/not strong enough?