I saw something that said "どうして長いかわからなかった私は..." and it got translated as "I didn't know what to do with my hands…". I would have thought it meant something like "I, who didn't know why it was long, ..." Is it an expression?
Where'd you get that translation from? I'm pretty sure it's wrong. What you have more or less means exactly what you thought. What's the full context? I feel like the part after 私は matters a lot :D
It's from a short comic by a British artist that was published in a Japanese magazine, so I'm definitely inclined to believe it's a sensible translation, but I'm just not understanding it! You can see the comic on Instagram here:
https://www.instagram.com/p/DX... part I quoted is in slide 3, and I'm including a screenshot
That's どうして良いかわからなかった私は with 良い not 長い, which would make sense for "I didn't know what to do with my hands". Literally it's more like "Not knowing what I should do, I...", but the English translation is a nice idiomatic way of capturing it given the context.
Would you like me to explain / break down the whole thing for you?
The whole thing is: どうして良いか分からなかった私 は、バッグを 握りしめて 、キッチンのカウンターに よっかかっていた。
— "Not knowing what to do, I was clutching my bag and leaning against the kitchen counter". And if you took 良い more literally, "what would be good/appropriate".