Maybe its a panic attack? I have similar feelings towards death, it is the end. No fearing death doesn't mean life has been awesome, or that you don't have hardships that doesn't make you want everything to end, it just is a sense of self-preservation or even self-love.
I fear the end, because I know that then ends the potential to change things to better my life, or enjoy.. the very few things I actually do enjoy. When put into numbers, it can be incredibly scary how already limited and short life really is.