The 1 series scored 5 stars in the euroNCAP tests.
I got whacked in The ass a few years ago. The car behind me hit the dead center of my rear bumper at somewhere between 20 and 30. I stopped at a light. He didnt.
Anyway same deal. Nothing obviously broken in the rear.
The damage ended up being the bumper. Exhaust. Carbon and evap canisters and the bottom of the trunk.
His car ended up being a total. His engine was on the floor and he couldnt open his doors. He had a then new Acura TL.
Two morals to this story.
1) these are built like brick shit houses.
2) low nosed cars can slide under the car and break the trunk. Check your battery connections (make sure they didnt move or the battery is compromised)
And as always your safety is the moat important thing. Good to hear it.