Is It Safe To Take Aspirin For Headache?

Was helping my husband build a wooden swing set. A wooden 4x6 40 lb beam fell and hit me in the back of my head. Put ice on it. There is a smaal bump which sticks out. I have a slight headache, pupils not dilated, no nausea. Can I take aspirin? I am a 61 year old women in good health. Ate dinner no problems.