carneasadud (@carneasadud).... Speaking only from experience, I am not any expert, I'd advise you to see a good ortho doc, one well experienced in shoulder problems- and get an MRI. The kind of pain you describe is the kind I had also in both shoulders, and it was one of the bicep tendons (in each shoulder) tearing and eventually rupturing. I hope you don't get to that point.
The bicep muscle splits and attaches to the shoulder in two places and the front is most often the one that tears or ruptures- and if it ruptures (comes off the bone), that bicep muscle drops and become blame near impossible to find in the mass of muscles. Here's a diagram and little explanation of their locations, attachments, and function, and possible causes of damage. https://www.miamiboneandjoint.com/biceps-insertion-rupture
I did P.T. to no avail but to my harm (no MRI had yet been done), and had to have the rupture repaired.

Wishing you good luck and speedy healing, whatever the problem is.