Your tax refund is not determined just by how much you make. It's determined by calculating the tax on your income, then subtracting out from that any tax you had withheld during the year. If the type of income you claimed changed from W-2 to 1099-MISC, the tax on that is higher.
Your refund can only be as high as the tax you had withheld unless you have a lot credits. If your income goes up, your tax goes up, and, if your withheld taxes didn't go up by as much as your income, you will get a smaller refund.