In all the time I spent in London, (during my ill gotten youth where I wandered the streets late at night, by myself), I walked home in the pitch black, through very unsavoury areas and was never mugged or even aproached once.
During the time I travelled many places/countries, by myself, I was never mugged.
When did someone attempt to mug me?
When I was nine months pregnant.
I was walking back from my firends, a street away from home, the only thing I had on me was a pack of cigarettes, with two in and a throw away lighter and my house keys.
When these two blokes aproached me, they threatened to knife me if I didn't give them money.
I held the keys in my fist, with the pointed ends sticking through my fingers, told them what I had on me and asked them if they really thought that them loosing eyes and having chunks torn out of them was worth it, they left very quickly.
The moral here?
Muggers pick easy targets.
If you don't look like a victim, then you won't be.
It wasn't brave what I did, it wasn't stupid either, it is what I do.
I say that I have only been mugged, but that doesn't mean that I don't know what it's like to have a gun/sawn off shot gun rammed in my face, or a knife flashed at me in an effort to intimidate me and I have reacted accordingly.
There is no set rule to what you should and shouldn't do, there should be no shame attatched to what you do when you are faced with that situation.
You fell for the oldest trick in the book, as soon as you stopped for him, he had you, whether he had a knife on him or not.
My advice is, don't feel stupid, a coward, or anything other than a person who was mugged.
Learn from your experience, then push it behind you.