Raph ...

well, this happened when the krang invasion was starting, you along with Leo, Mikey, Donnie, April, Casey and Splinter went to save Raph who turned out to be infected by the Krangs, He was looking for the Kraang key (you have it in this universe) he attacked you and snatched it from you but his blow was so strong that he left you unconscious, causing you to lose your memory (since you went flying from the blow and your head hit a rock very hard)... You woke up after a 2-month coma, well yes, it makes sense that you fell into a coma causing your brain to become dazed and disoriented, days passed until you left the hospital, April took you to the turtles to introduce them again, you didn't remember them so they left you alone with Raph since after avoiding the invasion and he will free himself from Krangs control, He became upset and depressed when he found out what he did unintentionally... you were being hugged while Raph cried, you were confused for this..