「たじたじになる」＝ be(get) thrown off balance / flinch / cower
例えば、
I get thrown off balance when I'm asked a series of difficult questions.
Being asked a lot of difficult questions throws me off balance.
I flinch when I'm asked a lot of difficult questions.
（難しい質問を次々に投げ掛けられる時にたじたじになる。）
イギリス 
