I am a 23 year old female, i have had pain going up and down my left arm for three days. no history in heart disease, and this came out of nowhere

Radiculopathy: At your age, and given your history, your symptoms are more likely to be from a pinched cervical nerve (radiculopathy) than from a cardiac issue. It would be reasonable to watch it for a couple weeks - most such symptoms will resolve with time. However, if you develop any other concerning symptoms such as chest pain, or if symptoms persist, do see a physician.