Is it wierd to develop a crush on someone who has recently died?

I would say you were just very take-aback by the death, I wouldn't say it's a crush. You are probably just wishing you had some time to get to know the young man, and your brain is just showing you this in a way that you connect with a crush. It will fade, so don't be worried about it at all, it's part of a grief thing for some people, feeling guilty to some degree about not getting to know the person before they died.