I play with blood frenzy and rampage
Fen play with necromancer's shroud

Fen put me at 1hp and the turn end.

Necromancer's shroud said: killed AT THE END of the turn
Rampage said: when opposing allie is killed, your hero heals 2 dmg
Blood frenzy said: AT THE START of each turn your hero take 1 dmg

my logic brain tells me that there should be a difference or a space between end turn and starting turn. Why not?

it is impossible for the start of a new turn to arrive before the end of the last turn. I'm confused