IYou should report the matter to your insurance carrier first. If a claim is made your carrier will defend you and be responsible for any settlement or judgment up to your policy limits. Good luck.
This is the second time you posted the same question, and the answer does not change by reposting it. Yes, you backed up and you're at fault. And that is why you have insurance. If the other driver was hurt, your insurer defends you and pays claims. So stop worrying. (Note that his speeding and seat belt may weaken his claim in that your insurer may argue BOTH of you were negligent, but they'll deal with that, so stop worrying.)
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