if you have the gold, buy dual specs - for a hybrid class, they're so useful its stupid.
i looked at your armory, dunno if you just logged out weird but some of your gear's missing. once you get it put back right. log out and post here and i'll try and help you figure out what to go on. i'm mainly an ele shammy, but i've got resto offspec and can heal anything 5man normal or heroic, though once i started healing it took me about 3 instances to really "get" what i'm supposed to be doing.
you always wanna keep ES on your target. if you're group is melee heavy, you'll end up using chain heal a bunch. try and get your ranged DPS to cluster and not spread out so you can use chainheal on yourself and it'll hit them as well, good for quick top offs. when topping the tank, use Riptide to get the tidal wave bonus and then use a healing wave to get him up, if he's spiking lots use Lesser healing waves till he has enough HP to survive for a sec then top off with normal HW. if the melee is taking damage or needs to be topped, use CH, usually 1 or 2 is enough to get them back into business. if your ranged doesn't wanna listen and spreads out, use LHW's on them to boost their HP. drop Wrath of Air, Flametongue, mana stream, and stoneskin totem (or tremor totem depending on if you know the encounter has fears in it or not) and just play whack-a-mole with the HP bars. thats all i can think of now.
edit:
noticed your spec. are you pvp healing or pve healing? for pve healing your spec is a bit off.
http://www.wowhead.com/?talent#hZ0xxIZx0euIxoxkrIRtthat is the spec i use when healing. glyphs i have Lesser healing Wave, Chain heal, and water mastery. this is for PVE healing only though.