Due to baby growing and expanding of uterus hence you will feel pain. If this persistent it is best to consult doctor soon. Do not miss out on meal period, it could be pain due to miss meal. It could also be due to active work/chores hence of the pain. Having said that, it can also be due to other reason that your doctor can better advice and thorough check. Meantime you can put ointment and massage your tummy and back.