After a crash, your safety comes first. Move to a safe spot and call 911...

https://dlf-ne.org/what-if-the-other-driver-changes-their-story-later-a-paralegals-guide-to-protecting-your-claim/

After a crash, your safety comes first. Move to a safe spot and call 911 immediately to ensure you get a police report. See a doctor right away, even if you feel fine. Take photos of the damage and collect contact info from witnesses