Try the following line of code, and see what exactly goes different than what you expect it to do.

//set -s % $+ $me on | echo -a % $+ $me

It will have echo'd: %<yournick>.

Since you want to check the value of %<yournick>, this isn't correct, which leads to the solution of your problem:

//echo -a $(% $+ $me,2)
//echo -a $($+(%,$me),2)
//echo -a % [ $+ [ $me ] ]

Try to figure out why exactly you need to do the three above solutions, typing /help $eval and /help [ ] evaluation brackets, will help you understand.