I have the same thing and I'm told I have bursitis.

On my hip it can. I wake up at times with pain after sleeping on my hip. Then I can just start walking and it hurts more. Maybe you did something in the day that didn't feel like much and then slept on it all night and major inflammation in the bursa. Google bursitis and see what symptoms and treatments they recommend. I'm allergic to anti inflammatories so have to ride it out. Takes longer to heal. Some people get a cortisone shot if nothing else helps. Definitely see your doctor if you can't get any relief. Hope this helps.

Moreen Gauthier can this happen just out of the blue as I have not been active at all I had it a couple of times before but never as bad as this I could bear the pain but haven't been able to this time

Thank you never heard of it but will look it up the pain has eased up a bit after liquid morphine but is still really tender to touch on outside of bicep and under armpit X

I was thinking bursitis because I get that in my hips but wasn't sure if you could get it in the shoulders. Glad you mentioned it.