Thanks for posting your query.
It sounds as though you could have strained or sprained your back muscle.
, most women are more prone to strains and sprains because of the pregnancy hormone progesterone
, which tends to relax the muscles and you are more prone to injuries.
You could try over the counter preparations like pain relieving ointments
. Apply gently to the area which hurts, but do not massage
If there is no relief in a couple of days, you can go and see your doctor for check up and prescription of oral pain killers.