I'm in the UK so just seen a GP (general doctor) no chance to seek a second opinion unless I go to the ER. I have to go back to him if the problem persists after 3 weeks.
I used the term ligament myself, I guess a better term should have been muscles and tendons. Anyway he just did the basic arm movements and felt around the shoulder. The only thing he ruled out was a full tear. When I asked questions about weather it was maybe a strain/tendonitis or partial tear he did not want to give an opinion and just kept saying come back in 3 weeks if it does not show signs of clearing up.
Usually for a non urgent case like mine a MRI can take months to a year from the date it was requested. I think GPs cannot request them and only specialists in hospitals can. A GP to specialist referal can take a month or more too.
I just have to hope its not serious otherwise it will be a long wait and convoluted process to get it treated.