I don't know what class you play or what level you are but I main a Resto Shaman and in MOP i mained a Holy Paladin. I know what you mean about healing getting stressful as I have done plenty of dungeons and raids where people don't know mechanics or just don't care and stand in whatever and die and end up blaming you. That is not your fault. Unfortunately, those people are toxic and there is no way around it.
Some things that really do go a long way to help with heals are food buffs, elixirs, higher ilvl and most importantly proper rotations! Download an add-on like Recount to see what your heals are like and try and see if you can improve your HPS. Watch some youtube guides.
They changed most pieces of gear to have two primary stats on it so you don't really need another set of gear on you. you should use your second spec for DPS. My resto shaman doubles as a ele shaman and i can solo all solo content without any real problems. you really shouldnt be trying to solo an apexis daily as a healer as that would take significantly longer. Use your secondary spec as a DPS spec to solo content. you really shouldnt need two healing specs. I just carry a bunch of tomes to change things on the fly but that should probably happen before most bosses when raiding.
I haven't pvp'd with my resto Shaman but my Holy Paladin was almost impossible to kill in PVP. I usually went with two friends for the big BG's and stuff. I didn't really kill people but you cant expect to do that as a healer in PVP.
Ultimately, it sounds like you don't like healing and would rather be a DPS so do that then.
This Subreddit has a healing thread dedicated to helping people try and learn the ins and outs of healing, you should check it out tomorrow!