Strange has a big fat weakness and that's called his inability to deal with any sort of mental attack. He can't stop himself as he starts walking towards a tree. But he can continue to try and figure out what the hell this magic is.

He's keeping his third eye going as he walks. Whatever this is, it isn't fae—that's good! So logically speaking, it's probably a carnival member fucking with him, which means that Strange is already planning revenge of some sort.

By the time he's gotten to a tree and is wrapping his arms around it, Strange decides that this is dumb. He changes tactics and starts murmuring a spell of disenchantment. Because his spellbreaking works best via dumb kisses and the closest thing to Strange's mouth is a tree, he's just continuing to mutter the disenchantment invocation, hoping that's enough power to push through whatever the hell this is.