Turn off your macro / add-ons that say "Player x calls out for healing".
As a holy priest, I am not here just to mess about. My role is to heal. If you're not getting heals it's because I'm struggling somehow. Maybe you got aggro when you shouldn't. Maybe we're all about to die. Maybe I'm silenced. But whatever - I don't need reminding that you need healing - it's something that I am acutely aware of. It's all I watch on my screen - those little grid boxes of dwindling health. I never see much else.
So - do your healers a favour and SWITCH IT OFF. If you don't you probably really will need healing because you can bet that I will somehow manage to overlook you on purpose. That or make a macro that says "Seph calls out for a tank / dps".
/weekend rant off