Age for frozen shoulder?

Hi all. I have had frozen shoulder symptoms for about 2 months. UK based. Saw physio about 3 weeks ago who suspected frozen shoulder and referred me. Today been referred by orthopedic team for shoulder MRI to check it is frozen shoulder as he said its presents as such but I am young to get it. I am 43 so most things I read say 40-60. I am also female and peri menopause. As we live with the NHS in the UK you do start to worry anytime they actually start investigating stuff and thinking the worst! Just wondering how old people were when diagnosed and is a shoulder mri normal form of diagnosis? Thanks