Attempted window break while driving near UH, how to stay safe?

I was at Scott and 45 today (by UH) in broad daylight at around 4:30 PM and a man walked in front of my car and started gesturing that he wanted a drink or alcohol. Having no money or any liquid on me I shook my head and acknowledged him and was as friendly as I could. He flipped me off while acting erratically and then pulled something metal from his pocket that I couldn't see fully, almost like he was threatening to show a knife. I continued to gesture that I didn't have anything and he then started approaching the drivers side and pulled the object out, to my knowledge it appeared to be a glass break tool (thick metal handle with a small white tip). I gunned it to get away as I heard it hit the window hard, not sure why the window didn't break but I'll count my blessings. Luckily there were no cars oncoming so I was able to get out of there, but this has brought a couple questions to my mind:

1. I know evading is the best option, but it's common at this intersection that I wouldn't have had a safe route and I drive a small car that can't hop a curb easily, so I could see myself being boxed in. I don't want to carry a gun, what would be an effective self defense weapon in such quarters if he had broken the glass? Seems like pepper spray could friendly fire if shot inside a vehicle. Grab arm and taser?
2. What was likely the point of this? The fact that he had this equipment makes me feel like this was the goal today… was this likely an attempted car jacking or just a theft?… or a person just being out of their mind?

Appreciate any thoughts, a bit rattled. I know what I signed up for living over here but it still sucks.