Be nice to me. I'm not feeling well.

我有点不舒服，对我好点。

《牛津词典》

For example, under the weather is an idiom meaning ill. So when people say "I'm under the weather", they are saying that they're not feeling well.

例如，“under the weather” 这个习语的意思是“生病了”。所以当人们说 “I'm under the weather” 时，他们是在说他们感觉不舒服。

youdao

I'm not feeling well.

我感觉不太舒服。

youdao

The old man was not feeling very well.

VOA: special.2009.12.26

Let's say that you're not feeling so well.

假设你觉得有点不舒服。

Don't 课堂 - SpeakingMax英语口语达人

Also,she had not been feeling well.

VOA: special.2009.06.27

But the family later said his travel may be delayed because he was not feeling well.

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"If I wake up not feeling well, I just figure I'll soon feel better, " says Ms. Taylor, 50.

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But after lunch Saturday, while resting, he was not feeling well, and emergency crews were called to the site.

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