Would taking a 65 mg supplement of iron a day help relieve pain &/or inflammation of my traumatized cherry angioma? I have been told I have low iron

Not likely. The pain from your angioma is probably unrelated to your low iron level. Taking iron may help your iron level, as well as eating iron rich foods (dark green leafy vegetables, lentils, red meat, etc.).
NO. Aware of no association of iron supplement to angiomas. Typically there is not pain or inflammatory reaction around the angioma. If you hit it or damaged the site, use of tylenol (acetaminophen) for discomfort is fine. See you physician to make certain it is getting better.
Probably not. I am not aware of a relationship between angioma and treatment with iron. Rarely, you can have larger vascular malformations that destroy red blood cells but this does not sound that severe. Treating the anemia is reasonable but iron supplementation alone may not be the problem. When taking iron. Some suggest concurrent vitamin c to maximize absorption and stool softeners to minimize constipation.
Iron. It's unlikely that taking iron can help with pain due to traumatized cherry angioma. Iron deficiency can be associated with chronic pain as in fibromyalgia or restless legs syndrome. So it can help in that kind of way if you are low in iron.