Dog in car - anxiety

Today at work a patron told me that there was a dag in a car and the windows were barely rolled down. A coworker of mine knew who the van belonged to, so she went to talk to them. They said the windows were cracked, and that there was a fan going. Apperantly the people who own the van are homeless. The original patron left, and when she left she had called the police to respond to the situation, who then talked to the owners of the van. I just feel so much guilt because I didnt do anything when I should have. I dont know how much the windows were cracked. Im not sure how the fan situation was set up. I am asuming the dog is ok, but I feel like if something had happened, it would be my fault. I am also worried about what the original patron who told me about it thinks of me. or since I was at work, what she thinks anout the pace I work for. I just feel like a garbage person who should have done more.