Holy? I Must Be Insane.

My brain must have been affected by running shadow all this time. I actually bought my dual-spec and came up with a holy spec to be a healer. What am I thinking? I think that I had my spec selected for about 5 seconds when the whisper came through, 'are you healz'? No time like the present I thought and joined the group. I did let the group know that I have majored in dps but was now trying to learn how to be a 'full-time' healer. I'm just trying to be more well rounded as a priest. Better to be honest with them. We headed to Old Kingdom where I did have some lingering quests to get done. Me, two death knights (still tripping over dk's) a hunter and a lock ventured into the instance. I must admit, I find old kingdom very challenging. I'm not quite sure why but I have found it to be one of the harder ones to do. We got around the first corner and almost on que the MT aggroed everything in sight and expected healing to keep up; it didn't. Our first wipe. I swear I need to make a macro that I can hit that says 'slow and steady'. What every happened to instance strategy? These days its' aggro everything and pray dps and heals can keep up. Aggravating but that's the wow world we live in. It didn't help that I had a new spec, had my spells in different spots on my bars and that this was my first real 'holy' effort. We got to the first boss and I was throwing heals like crazy. I put a prayer and renew on the MT and almost instantly he was at half damage. I started thinking that his guys spec was a little off. Dps spec is not a tank spec. I'm going to have to get a bit more knowledgeable on tank builds. If I'm going to be walking into a bloodbath I'd rather not get involved. The worst part of it was that I seemed to be running out of mana pretty quickly. I threw out the shadowfiend which gives me mana by the damage it does but it was too little too late. 2nd wipe. I couldn't believe the damage the MT was taking and how quickly he was taking it. I barely had time to get heals off to keep him standing. I even had this 'spirit' on him that is supposed to die in his place. I still haven't figured out that thing. The hunter ended up bailing and I did to. I felt bad but the group was not working out. This was my 2nd bad effort out of 3 in the last week so my healing confidence isn't sky high but I'm going to chalk it up as a 'learning opportunity' and keep rolling with it. I've been in bad groups as my hunter too but I've kept on shooting. I'm now halfway to 78 and I created my 'epic' flying carpet but I can't ride it yet; I only have to come up with the 5k to pay for the epic flying. Only 5k.