There may be more wires than you'll need to handle in the ceiling box. Take a moment to look for brittle or cracked insulation or any signs of excess heat in the box. If you see anything that doesn't look right, consider calling an electrician. If the wiring looks alright, follow the black, white and green or bare copper wires from the fixture to their connections to the house wiring. Gently work those connections down from the box so you can access them easily.