かと心配した

worried that

→ か
phrase Rare #22,408
worried that Used after a clause to express concern or anxiety about whether something might happen. Often used with のではないかと to mean “worried that...” or “worried whether...”.
JA: 試験に間に合わないかと心配した。
EN: I was worried that I wouldn’t make it to the exam on time.

彼女は列車に乗り遅れないかと心配した

She was worried that she might miss the train.

お前が怪我をしたんじゃないかと心配したんだぞ

I was worried that you might have gotten hurt.

現れないかと心配した

I was worried you wouldn't show up.

— レミーのおいしいレストラン (2007)