Edge of the night ( Spell block bug )

Has , I use to time-combo my Q-W to create a huge burst damage, but when Twitch used Edge of the Night Spell block , it hasn't blocked my Q or my W , it blocked both skills ( both timed at same time ). I haven't tried to use it against another champion , but I presume that if I threw my combo-timed Q-W on another Edge of the Night , it would block it also. When I combo with Q-W , damage aren't written separately , which makes me think they are taken as 1 single skill shot. I just want to avoid it happening again when I'm using my combo :0 . Thank you for your time