Translation guide
Expressing a low mood, sadness, or lack of energy in Japanese. The most common and natural ways are 気分が落ち込む (kibun ga ochikomu) and 落ち込む (ochikomu).
I feel down.
I'm feeling a bit down.
To say you feel sad, depressed, or in low spirits.
A natural, common way to say 'I feel down' or 'I'm feeling depressed'. Literally 'my mood sinks'.
I've been feeling down lately.
Verb meaning 'to feel down/depressed'. Can be used alone or with 気分が. Very common.
Literally 'my feelings sink'. A bit more literary or poetic, but still used in conversation.
On rainy days I feel down.
A noun/adjective meaning 'melancholy' or 'gloom'. Often used in the phrase 憂鬱な気分 (yūutsu na kibun). Slightly more formal/literary.
Literally 'my spirit is heavy'. Used when you feel burdened or reluctant, often about something specific.
A milder, more temporary sadness.
Onomatopoeic verb meaning to be dejected or downcast. Often used for a visible, mild sadness.
He was feeling down all by himself.
Slang/casual verb meaning 'to feel down' or 'to be depressed'. Literally 'to be dented'. Very common among younger people.
I got dumped by my girlfriend and felt down.
Means 'I can't muster energy/cheerfulness'. Often used when you feel listless or down.
I just feel down today for some reason.
Specifically when something didn't go as hoped.
To be disappointed, disheartened. Very common. Often used when expectations aren't met.
I felt down after losing the match.
To be disappointed, disillusioned. More formal than がっかり.
I was disappointed in his behavior.
落ち込む is the standard, neutral way to say 'feel down'. 凹む is slang and very casual, often used among friends. Avoid 凹む in formal situations.
I made a mistake at work and felt down.
I got a bad test score and I'm so down~.
Avoid directly translating 'feel down' as 下を感じる or similar. It doesn't make sense in Japanese. Use the expressions above.
試験に落ちて、落ち込んでいる。
I failed the exam and I'm feeling down.
憂鬱な気分だ。
I'm in a gloomy mood.
明日の会議のことを考えると気が重い。
Thinking about tomorrow's meeting makes me feel down.