<-- Catholic.
How old are you?
FYI..
If you want answers from actual Catholics about your faith (this probably doesn't qualify) it is best you ask them on an actual Catholic forum/website. Luckily, there is the largest Catholic forum in the world and it is located at:
http://forums.catholic.com -- Ask your parents if it is OK to sign up for an account.
I'd post your questions THERE, instead of a totally public Q&A message board where mainly non-Christians tend to hang out.
ANYWAYS...
1) If you did something out of ignorance, then your guilt or 'copability' is reduced. It isn't a mortal or 'intentional' sin if you didn't know. So what you did, out of ignorance, is minor.
I'd question your parents allowing you to grow up watching secular media and not instructing you that these things aren't real or appropriate to do -- but I digress, anyways...
2) Magic, like they portray in TV, isn't real. But it can lead people, such as yourself, to play around with or 'dabble' in it, which then CAN lead to one getting involved in the occult and demonic things. So it can be like a sorta 'gateway drug' (so to speak) to real magic.
So if you practiced it like you saw on "Wizards of Waverly Place" and "Harry Potter" -- then you haven't really done anything REAL. IF, however, you did research into pagan magic and the occult and DID attempt to control, communicate, and summon ACTUAL spirits, then you should go to confession.
3) You seem sincere in that you took steps to throw away the candles and such - that can serve as a sorta 'penance' or attempt to make things right. I would keep this in mind for your next confession.
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The reason that magic is wrong, in case the school didn't explain this to you, is that we, as Christians, should:
A) seek to do whatever is God's will, not our own. By doing magic, we are attempting to change outcomes to our own selfish desires, irregardless of what is TRULY best for us and what is therefore God's will for us.
It is therefore a sort of disobedience.
B) As Christians, we are taught to seek God for help and not try to supernaturally take control of things on our own. We are to say prayer and wait for God's answer in our lives. We aren't supposed to take extraordinary means to circumvent God and take matters into our own hands.
We CAN use natural means, such as our knowledge, our compassion, our love, and normal actions to do things, but we shouldn't be taking supernatural actions to try and force an outcome. It is one thing is we have the power to do something ourselves, but NOT if we need to try and use special powers or ask spirits/demons for help.
C) When God does something, he does it by his OWN power. When we involve 'magic' we are trying to control arcane powers outside of our own natural, God given abilities. We are in a sense, trying to play with something we truly aren't in control of. Most of the time we can't.. and when we succeed, it typically has results we didn't intend. We should not dabble with things which we don't possess or which aren't part of WHO we are.
God is beyond the physical (metaphysical) so he CAN manipulate, talk to, etc. spirits (the Saints, Angels, and Demons) but we are physical beings.. it is NOT our place to try and manipulate them.
D) So God has given us the ability to accomplish things physically here on Earth. If we need extra help, he wants us to come to HIM, not try to mess with things that we'd don't fully understand, on our own. Like a good parent, God says "here are the things I have allowed you to do on your own.. if this is not enough, come to me FIRST, before you try to do things on your own, which you don't fully understand."
We'd do good by following his command and not messing with the occult.