Help! minor rear end accident?

hi, i recently rear-ended someone. nothing more than chipped paint. i was probably going 1 or 2 mph. The man got out of the car to yell at me and i apologized and what not, but then he just took off. i was going to try and talk to him about what he wanted to do about the issue but he just sped off. At the time of the minor accident, i was freaking out and didn't think to write down a license plate or anything so i don't really know what to do. does this mean he isn't going to do anything about because he just left? anybody with knowledge i would appreciate it