Thanks for the comment, but I've thought of everything. I try very hard to keep his day to day fairly consistent, the only recent changes I can think of are - transitioning into a new class at daycare, but most of his friends were already in the class; and my brother moving back in with my parents who my son stays with on weekends. I'm honestly stumped at how these could affect his behavior, even more stumped because he is usually such a loving child - as I'm typing this he's snuggling up next to me asking for kisses. Sometimes it's so night and day.
Ask your self WHY what has happened recently that could have upset him, any new happenings new sibling, new daycare, new house, he told you he is angry find out the WHY ...good luck