Rear Ended someone, no police involved, whats my status?

What is the name of your state? Arizona

about a month ago, i rear ended someone at about 5mph, causing minor paint scratches. No visible dents etc. The police was not involved, and the only information exchanged was my phone number, name and address.

A month later, the other party calls up stating that the damage was $3000 and that they were going to file with their insurance company.

At the time of the incident, i was driving without insurance, however the vehicle was insured and i was driving since my parents could not take me.

I want to know how liable i will be, what will happen, if my insurance will cover it, if not what will happen, and more importantly, do they have enough grounds or information to actually proceed with anything. There were no witnesses or other parties involved. Me and the other driver, no passengers etc. Please Advise.