Hi Denise
As you know, I am a 'city girl' too (Ask Don he'll tell ya how it is here
) and reading your story, I think you basically did ok. While it is a must to be alert, don't get paranoid, been there done that, have a t-shirt. For one, don't stare off into space, be aware of your surroundings. If you see people like you did, DON'T say to them "You do not want to talk to me". It might egg them on. If they start getting near you, get up and move to a position where you will be able to do something should this person come at you. I like to have a little distance and make sure I am not backed into a corner or only have one escape.
As for mace, no you can't just mace someone whether they are high, drunk, or even saying something to you. You CAN have your hand on it (where it is unseen) and have it ready to go, but never just mace someone unless you are getting attacked. I carry mace with me but I also carry knives. I am very comfortable with knives and trust myself more with them than with mace. Mace is just kind of a back up for me.
I see gang bangers all the time at my grocery store and 8 times out of 10 they will start saying something or try to walk closer to me. I have my right hand on my knife, which is in my pocket (they can not see it), and it would take approx two seconds to have it flung out and ready
However, I would recommend if you carry a knife to practice opening it over and over and over again, do NOT carry it until you are comfortable with it. You don't want the BG snagging it from you. As you already know, this form of self defense was extremely useful when someone tried to steal my Christmas bags
So, IMO, I prefer knives over mace (of course I'd prefer my .380 but thats city life for ya).
Always have something with you at all times and something that is very easily accessable. If something should happen, you won't have time to fumble around in your purse trying to get it out, opening it etc etc. Be one step ahead at all times.
Just keep your head up and stay alert. Remember BG's normally pick the weak and non-attentive victim.
Good luck, stay safe, and try to enjoy life a little bit