There's certainly a cynicism present in some providers - we're definitely not a perfect bunch, and some areas will have more explicit policy on the use of narcotic pain relief.
For me: I look at physiological symptoms. You tell me you're in 10/10 pain (the "worst of your life"/"worst you could imagine") and you're in no visible distress with normal vital signs, then I'll factor that into the decision.
That being said, I believe it is unethical, immoral to withhold something that could benefit a patient who is in genuine distress, regardless of anything else. For those patients, we have options, too. Fentanyl, for one, is used a lot pre-hospital as it is both an effective analgesic with a short lifetime in the body.
There used to be (probably still is) doctors in the ED who don't want a patient to come in with pain meds onboard because they want to see a "baseline presentation". Again, I think this falls into the realm of poor provider care. We have diagnostic tools for objective analysis, and having a patient in pain just so we can measure it is inhumane.
Bottom line: if a patient requires pain medication, they will get it from me, subject to analysis of circumstances. In your example above, if it's not "drug seeking" but concerns about side effects, then the patient and I can have a discussion about benefits versus risks (the flip side to that being if a patient has a broken femur, for example, that conversation is likely to be limited to 'give me the damn drug!").