んじゃないかと心配

worried that ... might

→ の
phrase Rare #35,522
worried that ... might Used to express concern that something may happen or may be true. The んじゃないか part expresses uncertainty or worry, not a literal negative question.
JA: 電車に間に合わないんじゃないかと心配です。
EN: I'm worried that I might miss the train.

あした雨が降るんじゃないかと心配

I'm worried that it might rain tomorrow.

彼女が道に迷ったんじゃないかと心配です

I'm worried that she may have gotten lost.

君が迷うんじゃないかと心配

I'm worried you might get lost.

僕が君の重荷になるんじゃないかと心配なんだ

I'm worried that I'll become a burden to you.

間違えるんじゃないかと心配なんです

I'm worried I might make a mistake.