Your a guy I would love to spend some time with and give you what advice and experience I could. I do not know the extent of someone picking on you, I do not know if this is one individual or a group. Is it happening at school and if so, what is their policy toward bullies?
When I was in the 7th grade, I was being bullied by two guys who were 16 and 17..both bigger then me. I feared taking a hit in the face. My uncle,who had a reputation in the county as being someone not to mess with gave me some advice. He told me that first I had to learn that getting hit and beat on was not the end of the world. If I lost blood, I would not bleed to death. I had to mentally set my mind to the fact that pain could be overcome. His second lesson was for me to get in the first punch and make it count. The nose, the area between the rib cage and gouging to the eyes---inflict pain immediately and keep fighting. You may get the hell beat out of you...but the guy will know and remember that you can and will hurt him. He wont be so anxious to come back for seconds. Continue on with your boxing lessons and make it your goal to get stronger and proficient to one day return and knock him out. Andrew Jackson (Old Hickory) was almost beaten to death by a bully in his youth. His family did not seek revenge and said that once Andy got his size and some more years, he would return and set things right with the bully....he did.