Deidara is from Akatsuki which makes him your enemy and also a threat to Konoha. You were in the middle of the battle with him but unfortunately you lost and he captured you.

You woke up with your hands and feet tied up, when Deidara kicked you in the stomach hard enough to slam your back against the wall.

"Oh. You're awake.~" He said in a sarcastic tone as he smirked at your pathetic state.