My cartilage is infected for about a year now...?

If it was done with a gun then it sounds like you might have shattered cartalige. If it's been infected for that long then it's only going to get worse and lead to major health problems. Leaving an infection untreated can be highly dangerous. I suggest seeing a doctor or PROFESSIONAL piercer who uses actual needles to pierce for advice. If it's infected changing the piercing will be very painful. I suggest you begin disinfecting it, it will sting but it will clean out the bacteria, I'm sure if it's infected you will notice a strange smell coming from the ear infection too. Ideally, you should have consulted someone when you first noticed the infection, not a year down the line. If you manage to treat the infection (which is unlikely this far down the line) then I do NOT suggest keeping the piercing at all. Your body has rejected it and it is likely to become infected again.