Sound recorded in Audition sound different in After effects after importing

Can't help - nowhere near enough information about anything you've done. There is no file saving bug in Audition that I'm aware of - and I think I would be if there was. And if your recording sounds different in After Effects, had you considered the possibility that it might be an After Effects problem? Adobe's video software generally tends to be a bit flakier with audio than Audition is, across the board.

But if you normalize your voice file to 0dB, then that's what it will be - peaks at 0dB. If After Effects shows it as any different, then it's definitely their problem. Which wouldn't surprise me, because I believe that one bit of Premiere's audio system does something like that - imports files at the wrong level (at least it used to - I only ever present Premiere with finished audio, so haven't confirmed this recently). But without some actual numbers, we can't establish anything.