My dad was clipped by an 18 wheeler in an HEB parking lot and he got screwed. Good luck with the insurance but it sounds like yours should be pretty easy to see.
That is nothing more than a trucker not paying attention. I dont doubt that he didn't feel it, but he should have known your car was there and been taking extra care to make sure ho didn't get to close. Glad your Coworker saw it happen and let you know. Should be a simple fix.