It's impossible to answer your question without being able to look at your tax return, or without a lot of additional information. (Do not post your tax return. This is a public web site.) Your tax bracket is based on your filing status and your *taxable* income, not gross income. Taxable income is total income minus adjustments, exemptions, and deductions.
Also note that your taxable income is not all taxed at the same rate. Portions of your income may fall in different brackets. When people talk about what their tax bracket is, they mean the highest bracket that any portion of their income falls in. If your income is reduced, less of your income will fall in the highest bracket, or your last dollar of taxable income may drop into a lower bracket. But the portions of your income that fall in the lower brackets are still taxed at the same rates.
To complicate things further, if you have any qualified dividends or capital gains, those types of income are taxed at a lower rate than ordinary income in the same bracket.