I'm really sorry this happened. I hope it won't affect you badly. I have been in a similar type of situation three times. In one, I didn't see my friend dead, but his brother told me. In another, my long term neighbor died in a nursing home the morning after I had been to visit and I arrived with fruit and V8 juice he asked for. I was so shocked to hear he had died.
I burst out crying uncontrollably.

In another, my father had died and I wasn't meant to see his remains, but someone at the funeral home removed the lid of the coffin. I was so upset I thought I'd never stop crying and shaking.

There may have been more. It's terrifying and horrifying.