Chuck Palahniuk has an online workshop. Every 2 months he posts a "distinction essay," and this month it demonstrates physical sensation in a story, or "going on-the-body." Chuck P tells of an old saying in fiction writing: "When you don't know what happens next, describe the inside of the narrator's mouth."
His essay tells of how a mother used to draw a lot before her children were born, but after having kids, she developed sewing skills. One time, the youngest boy wanders into the sewing room, sits on the mom's chair, his legs and feet too small. He then jumps off the chair, lands on the floor, smack on a needle that pointed straight up. Blood everywhere. Spray. Hop. Spray. Hop. You could feel the blood spilling all over, shiny and sticky sweet.
More: "It's one thing to engage a reader mentally, to enroll his or her mind and make them think, imagine, consider something. It's another thing to engage a reader's heart, to make him or her feel some emotion. But if you can engage the reader on a physical level as well, then you've created a reality that can eclipse their actual reality. The reader might be in a noisy airport, standing in a long line, on tired feet, but if you can engage their mind, heart, and body in your story, you can replace that airport reality with something more entertaining or profound or whatever."
So no abstract words to describe pain or pleasure. You can't order a reader to feel the sensation. Provide detail after detail after detail, smell after smell, unpack the events in the reader's mind. The goal is to make the story happen in the reader's mind, heart and gut.
When you get sick, take notes. The hardest job a writer can have is to give a character a headache. And then this: "When you don't know what happens next: Have sex. Get sick. Get hurt. Or hit somebody."