Sivir Spellsheild against pyke q bug

Pyke was charging up his q, i saw this and decided it'd be an easy mana get with sivir's e. I got my spellshield up and then pyke's q hit me, it didn't do the damage but the pull still proc'd. We tried to repeat it but it didn't happen again, every other time the spellsheild would work properly. Some of the things that were happening was we were near their tower and i believe i had taken a towershot, so maybe sivir's e registered the tower shot as an ability hit so the pull still proc'd. That or the E registered the damage from pykes q as its own move, making sivir's e proc and then get pulled.