Fortunately, I have never had to work on a computer with the two-button mouse, not for a long time.
Fortunately, because I have naturally developed a healthy habit of using my left hand to do keyboard shortcuts while carrying on with my right hand - adjusting the viewed part of the document etc. This simple trick takes a lot of stress off your mouse-moving hand, but if you are too used to working with a two-button mouse the stress is doubled.
Quite often I see advice which includes 'right-click on your mouse and...' Instructions like this have baffled me so much that eventually I put a sticky on my computer to remind me of the one-button (or, these days, no-button) Mac-mouse equivalent of the 'right click':
which, of course, opens the options menu on the screen.
But, honestly, if you've just switched from Windows to Mac, try to get rid of your two-button habit - and avoid repetitive strain syndrome.