You know, there is a famous quilter out there (sorry, can't remember her name offhand) who does not press seams as she goes and teaches her students to do the same. Someone posted on the old board that they tried a block both ways, and it was just as accurate not pressing! Might be something to consider trying, in order to cut down time at the ironing board.
Would turning a crank aggravate your shoulder? Now might be a good time to invest in an Accuquilt Go!
My concern would be that periodic re-irritating the shoulder will delay healing. Gentle exercises would be good, but not tasks that cause the pain to flare up again.