I'm Sorry, Brother... [COMPLETED]

Chapter 1: Regrets

It was the start of another training session in turtle's lair. It was sparring session where Michaelangelo was fighting against his older brother Donatello and Leonardo was fighting against his younger brother Raphael.
"Ya ready to lose, fearless?" - Raphael said while spinning his sais in his hands.
"I am, but not to loose!" - Leonardo added.
"Ajime!" - It was the sign to start given by their sensei and their father Master Splinter himself.
The fight was going normally at first, where one was attacking and the other was defending. Raphael, however, was trying to knock his older brother off balance by spinning his arm and pulling him down on the ground, but that didn't go as planned. He calculated the distance badly which caused him to not defend Leonardo's attacks. Leo took the chance and punched Raph down, pinning him to the ground. Raphael was not happy about that.
"Grrr..." - He growled to himself.
"Good job, Leonardo. Raphael, you made a bad mistake, you should train more like your brother." - Master Splinter said after the fight ended, looking at Raphael with a strict look.
"Hai sensei." - Leo said.
"..grr...yeah, sensei." - Raphael said while getting up and glaring at Leo.
"That's enough for today, my sons." - Splinter said, "You can go now."
"Thanks sensei!" - Michaelangelo said happily as he exited the dojo with Donatello who was following behind him. Raphael and Leonardo exited after them as well, but Raph was keeping his fists clenched. Leonardo noticed his brother's behavior as he approached him worriedly - "You okay?"
"NO! I'M SICK OF THAT!"
"Sick of what?" - Leo asked.
"SICK OF THE FACT THAT HE'S COMPARING YOU WITH ME!"
"What? He's just giving you advice to train more!"
"SHUT UP, SPLINTER JUNIOR!!!"
"Raphael, stop it!" - Leonardo was trying to calm down his angry brother.
"DON'T GIVE ME ORDERS!"
"I am your leader!"
"YA ARE THE LEADER WHEN WE'RE AT PATROL AND NOT AT HOME!"
"This temper is getting to you, it'll get you in trouble if you don't calm down!"
"UGGHH, SHUDDUP! YOU KNOW WHAT?! I'M GOING NOW!!" - Raphael finished their arguement by leaving Leo and running to the garage. He takes the motorcycle and drives away quickly, not turning back to face any of his family members. He just knew he had to leave, and so, that's what happened.