I think the sadist thing about piercings is that most people don't know the worst way to get your ear pierced is by a gun, which is used my many places such as Claire's, Wal-Mart, and other places that only do lobe or helix (aka cartilage) piercings.
Healing time will of course take a good bit longer then regular lobe piercings since the cartilage is harder to heal. Also, it takes different amount of times for different people to heal. I've just got a snug, and its going to take between 8-12 months to heal. When it feels painless, and you can move it with no problems then its healed. Remember though, they heal from the outside in. So it could look fine, but still take care of it and baby it, until its painless. But the recommended time before changing it is around 2 months.
If you think its infected DO NOT TAKE IT OUT. Go see your doctor, and get some anti-biotic, or salves for your ear. If you take out the earring, your risk the chance of getting the infection stuck in your ear.
Also, you may be having more problems with your ear because you could be allergic to the metal. The best type to use would be titanium which is completely hypo-allergenic.
Hope this helped in some way.