I would suggest waiting a week or two, before worrying about the color. For reasons I don't fully understand, pools can open green and clear, but then turn blue after a week or so. Iron can do that, but I haven't always seen the characteristic rust colored backwash that would be expected.

Do NOT add calcium when the pH is higher; it is MUCH better to do so when it's low. However, I should ask, why do you need to add calcium? It's ONLY needed on inground concrete pools -- is that what you have? Even then, once your pH goes up, your TA will rise as well. With values of pH=7.6; TA=120; CH=150, your water is plenty close enough to 'perfectly balanced'.

BUT, if you do add calcium, never add a complete dose at one time. Multiple small doses are much, much less likely to result in your pool looking like milk!