It's on my right arm, about two inches above the elbow, on the medial edge, the side that would normally rest against my ribcage.
When I feel it with my left hand, my right arm tells me it's a bruise, but my left hand tells me it's a free-floating fatty lump. It hurts.
If it's still there in another few days, I'll go and get some doctor to feel it.
Oh, and in other news (and thanks to