Suggest Treatment For Pain In Arm After Injury

I was walking outside and pushed past a tree branch that ended up flying back to me and hitting my arm. my arm started hurting really bad and I couldn t move it much. The area was slightly swollen, was red and very hot at impact. Just a few minutes later the sides of my ribs started hurting for about two to three minutes. Like, it hurt so bad it was painful to breathe. It eventually went away and the arm pain lingered. It s been quite a few hours (6 hours +) and it still hurts to move my arm and fingers and doing so makes my arm very tired. There is now just a red mark on my arm but the pain is still there and has not dulled since. I can t tell if I have a rash/some sort of allergic reaction/or maybe the branch just hit me hard enough to leave this impact. Any idea as to what I m experienceing would be great!