Hi and welcome to SR, I am the mother of a heroin addict.
If you read the stickys above and read any and all info you can regarding addiction you will be able to answer alot of your own questions.
regarding your age, addiction doesn't care and neither do we. Addiction attacks anyone and everyone.
knowledge is power keep reading and good luck there are so many very smart people here that can give you so much guidance and support that you won't know what to do with it all.
Dealing with addiction (if you so choose) is a long process.