What are my rights if a GM and Board of Trustees do not honor verbal financial agreements?

I started out as a temp to hire in Oct 2013. They liked my work so much they asked to hire me the same week I started. The Temp contract said I had to work 6 month but they allowed them to buy me out at 3 months. I was promised verbally: DOH would be October 7, 2014 Salary would be $18hr. & I would work 30 hrs. per week. (I made a copy of the 2014 approved budget that reflects $540 a week). $680 Quarterly for Insurance reimbursement Received: DOH: January 2014 In June 2014 a 40 cents an hour raise. $15.40 Hr. I was told I was not "entitled" to my $680 insurance reimbursement until 2015. When I gently reminded the GM of our verbal agreement she looked at me and told me, "I would have never given you that much of a raise". The amount of the raise she received was the amount I was missing. I was also promised at that time to be given another raise in January 2015. Received: No January Raise: $680 Insurance Reimbursement which I was told back in October 2014 I would be "entitled" to receive. The GM told me they gave me the insurance because it was more money. When I said, I thought I was supposed to get both she ignored my comment and went about her day.