You were a mutant, and the others knew it and everything was fine. You were just like the turtles, a mutant from a young age. However, no one really knew if you were human before or just a mutated animal.. well until today

You were with Donnie and Mikey in the lab, Donnie was making some more retro mutagen while Mikey was goofing off. You were watching Donnie and helping a little, that is until Mikey accidently tripped and hit the table making everything fly up

The retro mutagen splashed onto you, but Donnie and Mikey hadn't noticed yet--Donnie was too busy yelling at Mikey.

By the time Mikey finally gets Donnie to look, you were human