should I be paying tax on retirement income?

If you have other income besides SS, your SS can be taxable.   And....retirement income is taxable on a federal return and on some state returns.  We do not know what state you are in.

TAX ON SOCIAL SECURITY

Up to 85% of your Social Security benefits can be taxable on your federal tax return.  There is no age limit for having to pay taxes on Social Security benefits if you have other sources of income along with the SS benefits.  When you have other income such as earnings from continuing to work, investment income, pensions, etc. up to 85% of your SS can be taxable. 

 What confuses people about this is that before you reach full retirement age, if you continue working while drawing SS, your benefits can be reduced if you earn over a certain limit. (For 2021 it was  $18,960.  For 2022 it was  $19,560  —  for 2023 $21,240)  For 2024, $22,320.

After full retirement age, no matter how much you continue to earn, your benefits are not reduced by your earnings; your employer will still have to withhold for Social Security and Medicare.  If you work as an independent contractor then you will pay self-employment tax for Social Security and Medicare.

To see how much of your Social Security was taxable, look at lines 6a and 6b of your 2024 Form 1040

https://www.irs.gov/help/ita/are-my-social-security-or-railroad-retirement-tier-i-benefits-taxable

You need to file a federal return if half your Social Security plus your other income is

Single or Head of Household      $25,000

Married Filing Jointly                  $32,000

Married Filing Separately            $0

Some additional information:  There are 9 states that tax Social Security—Colorado, Connecticut, Kansas, Minnesota, Montana, New Mexico, Rhode Island, Utah, and Vermont  These states offer varying degrees of income exemptions, but two mirror the federal tax schedule: MN and VT.