To help or not to help

So on Friday, as I was about to leave the office and I got into my car, this guy comes up to me. So I roll the window just a tiny bit because y'know, roll it down too much and he can swoop in and open the door from inside and that's a situation I've seen in dramas and don't wish to be in.

He asks if I can drive him out of the parking lot and to the nearest convenience store because he has this heavy tyre that's gone flat and he needs help. I don't know why a convenience store because he was probably looking for a tool or something and the security guard (who was with us the whole time) told him he could find it at the convenience store. It's literally just 2 lots from my office and you can just walk up. So I asked him (without wanting to look/be too rude) "But why can't you just walk...?" and I felt so shit after asking him that because obviously I'd like to help him out and he explained his situation. He genuinely looked like a nice guy and he was panting from dragging his, I assume to be, heavy tyre. So I kinda reluctantly said yes and he put his tyre in the boot.

But I knew a guy colleague who hadn't come down yet from the office whose car was just next to mine so I suggested to this guy that "Hey, my GUY colleague is coming down any second, maybe he can help you out instead?" and he was all ok yeah sure no problem, i just need someone to help me out with my tyre. 

And the whole time this is happening, there's a security guard with us who was helping him find a situation before that so I guess that comforted me a bit. It looked more legit I guess. But ultimately, he sensed that I was very uncomfortable with the idea of driving him up and he said it's fine, he'll just manage. I apologised profusely but he said "No, it's fine, I completely understand!" and was very nice about it. He then continued to drag/carry/struggle with carrying his tyre upstairs. 

So this is my dilemma. In the world that we live in where we listen to all sorts of stories and how literally everything can potentially be so dangerous, how does one be nice and generous without also at the same time, fearing for one's safety. I really wanted to help this guy out because he seemed nice and he even invited me to his brother's wedding (idk how it got there but i mean ok) and he really looked like he could have used a hand with the tyre and all but such a huge part of me was saying no and i should be better off feeling safe than sorry. So I basically told him no thanks i can't help you because you might be really dangerous. And he was very understanding about it which was even sadder about the whole situation because he probably knows it was a long shot to ask a lone female driver in a rather empty parking lot for help but still did anyway because he really needed the help.

I'd like to be nice and accommodating but I also don't want anything to happen to me. It wasn't his fault that I couldn't help with his situation. It's a different world we live in where you doubt everyone around you. What if I was in his situation?? And really needed help? Sigh. I know we always have to be kind and helpful but what if it's to the cost of our own safety. And vice versa; we always have to be careful and wary of our surroundings but would that essentially mean we'd have to give up on helping others out. 

xx