I would second this. I was told I had a bursa issue and it turned out to be disc related, impinging on nerves causing symptoms which were similiar to bursitis. I’m wondering what a GP did to say it was bursa related, unless you have done a bunch of testing to narrow that down.
Not being skeptical but there are just some bad (or not as good) doctors. There is nothing worse than hunting for root cause, some medical professionals are far better than others. You can always ask for an ultrasound to ensure it is in fact bursa related. Once you know root cause of what the issue is treating the root cause is so much easier than guess and test. Not that I am advocating rushing to imaging as first step, but if you find that things are not progressing its always good to get confirmation through testing and imaging. I wasted 18mths guessing and testing to learn I had disc issues. As soon as that was confirmed I was immediately confirmed for surgery and pain free within 90 days.