How do I know if I need recovery?

Your asking. Just by the fact you are asking the question i suspect you need it. But in all honesty good for you to be at least thinking about it. Past that i dont know from what. Talk to your doctor or counselor. Short answer, recovery is a different way of life and can affect how you handle any situation better and without a substance. Not a bad place to be. Lots of people ready to help as well.
Recovery from what? I will assume you are talking about drug and/or alcohol addiction. If you are asking the question, my best guess is that you do need it. If drugs/alcohol are getting in the way of your life, you cannot control its use, you are spending more of your time involved in its use, it is intefering with social functions (job, family etc) then you have a problem. See a counselor or your doctor to discuss.