@harborside24, you are certain to understand the allergy to steroid medication far better than I do. But, if you are on prednisone, you might switch to dexa or betamethasone. Often it is the preservative or binder that is causing the reaction.
You are wise to consider damage to the bone. All the bisphosphonates carry the risk of osteonecrosis. The jawbone and the lower aspect of the femur are cited areas of risk. And although Reclast is a stronger ( and more effective infused) dose of bisphosphonate, osteonecrosis is uncommon and seen (normally) after years of use. Prior use of oral bisphosphonates, Prolia or Evenity would put a person at increased risk.
Pain at the upper segment of the thigh bone below the hip joint would indicate the need for imaging. Objectively it is reassuring that the pain is moving around. Subjectively, unless it feels muscular, ice packs are helpful to chase the pain especially when trying to sleep.
Bless your trip.