Originally Posted by
molehill
I've had many blackthorn injuries when I was younger, in my hands from working with them (forestry clearing work). They are notorious for becoming infected so what you have is quite normal, we used to dread having a thorn in our fingers or hands as they often swelled up and went bad. There is something on the tips of these thorns in particular that does not agree with the human body :eek:.
What usually happens and looks like has from your photo, is the very tip of the thorn breaks off inside the foot, you may htink you have it all out but I bet there is a tiny bit left in there. The infection should clear up with the antibiotics but one day the tip of thorn will find it's way to the surface and you can heave it out. Maybe days or weeks.