What happened to my poor headlight?

I have an 87 Accord with the super duper cool hide-away headlights. Anyway today while deployed I noticed that my passenger side light was burned out. No big deal right? But on closer inspection I noticed that the housing isn’t closing all the way either, say , 90% i.e. it isn’t flush with the front of the vehicle. Also I noticed a small dent in that area that I never noticed before. What could have caused this, a run-away grocery cart? I’m bewildered.