Retirement tax questions

I would not file an amended return.  I would to see if the IRS takes any action, which I doubt they will since it does not change the amount of tax.  For Pennsylvania, if the distribution was considered taxable income for PA due to reporting with code 7 (if you were under age 59 1/2 it would be) it would not be taxable with code 4.  For more information, see the following from the PA Institute of Certified Public Accountants Taxes on Retirement Income: Pa. Treatment of 1099-R Distributions