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headache
昨日からひどい頭痛がして辛いです。
I've had a terrible headache since yesterday.
昨日から頭痛がひどくて、薬を飲みました。
I've had a terrible headache since yesterday, so I took medicine.
ストレスで頭痛が起きやすい。
Headaches are likely caused by stress.