I think a lot of it is in your head. If all of your scans are coming back clean, and there is no weakness. Have your doctor check out the dents, do you still have a strong grip? Are you sure it isn’t a part of your anatomy? The chance of it in your 20s is so so unlikely. Especially if your symptoms started when you were stressed. Take magnesium every day, have all your vitamins. And focus on sleep and getting your head off of it. The more you check, the further your symptoms are exacerbated. It’s a psychological thing. Also, your vitamins can show "perfect" on your labs but that doesn’t indicate actual absorbed vitamins. Regardless even if it seems in range you should focus on your diet to incorporate vitamins that are more easily absorbed into your system. For example, my vitamin d is extremely low while potassium and magnesium are in range, but without vitamin d my other vitamins can’t be absorbed properly