Hello, I have had both hips replaced and am now going through similar groin pain on both sides but mostly on R. I have been diagnosed with iliopsoas tendonitis and now iliopsoas tendonapthy after cortisone injections and PRP(platelet rich plasma) injections have not helped. I wonder do you have a tendon issue? I'm 4 years out from my right hip replacement. Research these diagnoses and see if it sounds like your symptoms. I am now most likely going to have a tenotomy because I can no longer stand this pain and disability. I can no longer drive because of it. It is not uncommon to occur after a hip replacement and is also known as snapping hip syndrome. Do you sometimes feel a "snap" or "pop" toward the inner groin? Especially when lifting your leg? The iliopsoas tendons are hip flexors so they help to raise your leg to walk up stairs for example. I just avoid stairs at this point!
Even pain medication doesn't really help this type pain. Muscle relaxers help most. If you lay on your side with legs bent in bed, you are flexing the hip and stimulating that tendon so it "fires" it up. I can only comfortably lay flat on my back because of this. I can't even sit. Any bending(which is flexion) of my leg causes pain after only a brief time.
If this is the problem, the good news is that if treatment is started timely, it may be fixed non-surgically. Most definitely get another Dr!! God bless you and May He help you get well soon!