be killing (one)

1. To cause one a great deal of pain, as of an injury or body part. Ugh, this ankle sprain is killing me—do you have any Advil? Phil's back is killing him, so he went back to the hotel to lie down. Can we sit down soon? My feet are killing me.

2. To cause one a great deal of stress, anxiety, difficulty, etc. A: "The professor said our test results would be posted online sometime this afternoon." B: "I know—the suspense is killing me!" A: "Sorry, I still don't have the reports ready." B: "I told you I needed those for today's meeting. You're killing me here, Tom!" My son hasn't called to check in yet, and it's killing me. I hope he's OK.