Rubber banding?

I'm not sure if this was a bug or just an issue with my computer. If it was a bug, it was gameplay related. In my most recent game, I was playing Riven against Poppy. Twice, I dashed before the enemy Poppy used Heroic Charge, and the resulting angle should have allowed me to avoid a wall stun. However, when Heroic Charge's animation began, I returned to the point where I used my dash, getting stunned as a result. The first time, I used Valor and was stunned into the wall to the right of the blue outer top turret outside of range, and the second, I used one of the first two casts of Broken Wings and was stunned into the same turret, though it was destroyed by that point. I died as a result of the second instance.