Sounds like you have a valid. You need to discuss this with an employment lawyer to see whether you should wait for the DOL to recover for you or whether you should pursue a claim.
Paying an individual as an independent contractor instead of as an employee can be a violation of several different laws, for example, unemployment benefits, federal tax law, state overtime laws, etc. The particular circumstances of your situation will determine the type of claim you can bring against your employer and thus the amount and type of recovery you can expect if you win. You may be able to bring a class action suit, but that depends on the particular circumstances. In addition, if the state department of labor obtains a recovery for you, you may be asked to sign a release of all of your claims, which will prohibit you from bringing a lawsuit against your employer. Please feel free to contact me, and we can discuss whether it makes sense for you to bring a lawsuit against your employer separate and apart from the state department of labor.