Part of what I was saying was that there are two different tendon issues possible. I had psoas tightness and pain after both THRs that resolved by the 3 month mark with no injections, etc. The first never had another issue. The second was fine for a bit but then started having problems that started small and ramped up over time. Many surgeons don't seem to want to recognize this issue so it took me a while to find a new surgeon to diagnose it. In the meantime, they tried injections into the psoas near the spine, PT, muscle relaxants, pain meds, a heel lift, rest, etc.
So, while an injection might be helpful now in helping it to settle, you may just be experiencing normal issues with the muscles having been stretched and irritated that will go away without other significant intervention being necessary.
It's hard, but try to be patient and give it a chance to resolve. Even the cortisone injections can be stressful to the body, so many surgeons don't want to jump to that too quickly. If this doesn't resolve, surgery is still there. That's the big gun, though, so more conservative/less invasive/less expensive options (including letting the body heal itself) are generally tried first.