Hi,
I'm not sure if this is a unique situation, but I wasn't able to find any reference to it on previous posts or anywhere else online for that matter.

3yrs ago I made a $5000 after-tax contribution to my Roth IRA. I later found out that I was not allowed to contribute that year due to exceeding the household income limit, so I converted the entire contribution to a traditional IRA.
For 2015, we will be able to contribute to a Roth since our income is now below the limit. My question is, if I convert my traditional IRA back to a Roth this year, will I be taxed on the the initial $5000 (which was the after-tax contribution originally)? Seems like I will be taxed twice in that case.

Appreciate any advice. Thanks for your time.