simmer - To heat a liquid, usually a stew or soup, just below the boiling point, allowing it to cook slowly; or to stay in a slow, controlled state of progress or tension, often before a larger event or change occurs.

He was simmering with anger, but he kept it inside and didn't say out loud what he was thinking and feeling.
paltry - A very small amount of something, indicating that it has little importance or worth

One day John spoke to his friends with anger as they were going down into the mine, "How does the company expect us to support our families on the paltry wages they give us?"