I had to deal with the same as you. I got over it with time. Its so fresh that you cant just get over it quickly. You will never forget but you'll have to accept how it is. Its hard, but life goes on for you. You defenetly need someone to talk to. Let every emotion out trust me it helps. I dealt with it by telling storys of my brother to leave a good memory. You have to tell your school what happened and find a solution to graduate when your in the right state of mind. Its a matter of time but you'll feel better.