How can I get my lost wages from an auto accident?

Whose insurance company? Yours or the other driver's?  Your company owes you a duty of good faith. The other driver's company sees you as the enemy and doesn't want to give you the right time if it does not have to. They can contest liability and argue over damages.

The only way the other driver's insurance company is likely to pay more than the bare minimum is if you have a lawyer.  If you were out of work for 3 weeks, were in pain, and especially if there is any residual damage, you may have a far more attractive case than you realize, and auto accident lawyers almost always provide a free initial consultation and would charge you only after they recover money for you by way of settlement and then based on what they help recover for you. If the case is "too small" the lawyer will tell you. Check out www.AttorneyPages.com.