Denying benefits/payroll change

I was denied full time benefits when the company did an addendum. I've seen an attorney who confirmed under the terms I was hired as well as the new terms I qualified under both.
This affected my vaction, personal days, sick pay and holiday pay for my 1st entire year.Instead of getting 7 1/2hrs on these days, I only got 4 1/2hrs pay.
They then did a payroll change that resulted in everyone only getting 3 weeks pay in a month rather than 4 weeks. I can prove on all counts through documentation, what this company did and how. The Attorney I spoke to, does not want to file a class action and feels the amount I'm owed is to small to pursue (-$1,000.00).
The attorney has confirmed, they were in violation of not paying overtime as they should have and did deny me my benefits regardless of which plan you look at. He was uncertain about the missing weeks pay as to whether or not it was unlawful.
This is a large company with locations in other states. This not only affected people in this state but another 10 to 15. Any suggestions would help. Thanks for your time