Your co-workers may begin to resent you if they feel your personal calls are taking time away from your work. Put yourself in their shoes
I'm planning my upcoming wedding and while I try to be discreet about it, I can sense my co-workers' eyes on me while I talk to the wedding planner, the photographer, and the caterer from my office phone. Can't people understand that a wedding is a once-in-a-lifetime occasion? I'm working as hard at my job as I am at planning my wedding, but I feel judged. Any advice?
Best wishes on your upcoming wedding, which I'm sure will be perfect. It may be the case that your teammates believe (justifiably or not) that your work will suffer (or is already suffering) because of your wedding-planning activities. Certainly if that were true, it wouldn't be the first time in history that has happened. Is it possible for you to move some of the wedding-related phone traffic to your cell phone, so that you can make calls from your car, or during your lunch hour, or from the train station?
If you imagine an alternate scenario—say, if one of your colleagues were suddenly (and visibly) immersed in planning for an upcoming personal event, and seemed always to be on the phone in connection with it—teammates wouldn't love that, either. Take pity on them, make your own life easier, and cut the wedding-related phone calls from work in half, at least—and your colleagues will be that much happier for you when the big day arrives.
Or use e-mail!