How are you a qualifying spouse? When did your husband pass? Do you have a child?
You can file a Joint return the year your spouse died. For the next two years following a husband's or wife's death, the surviving spouse can file as a qualifying widow or widower if they have a qualifying child. That basically lets you continue to use the same tax brackets that apply to married-filing-jointly returns. After the year of death if you don't have a child you file as Single.
See the eligibility rules at the bottom of page 10 of IRS publication 501
https://www.irs.gov/pub/irs-pdf/p501.pdf
