Is there a reason you think you did something wrong? Perhaps there is a rule that says one must be 18 to receive unemployment benefits, but I haven't heard of this. If you were legally working and your employer made the mandatory contributions to unemployment, then I'm not sure what you are worried about. Perhaps you can clarify the reason for your concern.
If you are eligible for unemployment benefits now, go ahead an apply. If there is a problem with what happened when you were 17, you can explain that to the California Employment Development Department (EDD) either during the application process (during a phone call from EDD) or in an appeal (if you are denied).
twitter.com/MikaSpencer *** All legal actions have time limits, called statutes of limitation. If you miss the deadline for filing your claim, you will lose the opportunity to pursue your case. Please consult with an experienced employment attorney as soon as possible to better preserve your rights. *** Marilynn Mika Spencer provides information on Avvo as a service to the public, primarily when general information may be of assistance. Avvo is not an appropriate forum for an in-depth response or a detailed analysis. These comments are for information only and should not be considered legal advice. Legal advice must pertain to specific, detailed facts. No attorney-client relationship is created based on this information exchange. *** Marilynn Mika Spencer is licensed to practice law before all state and federal courts in California, and can appear before administrative agencies throughout the country. She is eligible to represent clients in other states on a pro hac vice basis. ***