I would take magnesium and potassium in the morning and calcium and vitamin D at night.
I've found massaging all the areas around the sore spot can be very helpful. I have a 10-day-old problem with my neck, from handstand pushups I believe, After a few days, the source of pain traveled down to what I thought was a knot somewhere behind my shoulder blade. I looked up pinched nerves, and it said commonly a nerve in the neck is what causes the back pain. I've been massaging my neck and getting better results almost immediately. Try working all the other muscles around that spot- it may help, it may not