I Have Pain In My Ulna About 1-2 Inches Down

I have pain in my ulna about 1-2 inches down from the elbow. It is tender to touch, and if I put pressure on my forearm, like from leaning on it, I get a sudden, severe shooting pain that goes about 2/3 of the way down the ulna. It resolves as soon as I take the pressure away. No injuries, no pain or swelling. I have very well-controlled Type II diabetes and a remote history of metastasized thyroid cancer, with no abnormal blood markers. I am a 63 year old very active female.