Recharacterization of IRA contribution

On March 1st of 2019 and before I filed the 2018 return I mistakenly made a contribution to my Traditional IRA.  I intended to make the contribution to my Roth IRA.  I discovered the mistake on March 7 and re-characterized it as a Roth.  The actual amount that was re-characterized was $32 less than the original contribution due to a decrease in value.  My 2018 tax return was filed on March 10 with no deduction for an IRA contribution. I received from the Broker a 1099R reflecting a distribution for the original contribution less the $32 decrease in value with a code R in Box 7.  Turbo Tax tells me  I need to amend the 2018 return. My question is what do I change in the 2018 return? And as for my 2019 return should it include anything about the contribution since it was actually a 2018 contribution even though it shows up on a 2019 1099R?