Hello, Thank you for asking your query at DoctorSpring.
From your symptoms of pain in lower back and hip points out to dysmennorhea.
Dysmennorhea is painful menstruation that can start from ovulation and maybe continue till end of menstruation. Therefore, you can expect your period to start in a week or two. It actually occurs due to hormonal changes that occur.
There is nothing for you to worry. You can use Meftal spas, a anti spasmodic agent. This will reduce your pain or you can use OCP pills to postpone your ovulation.
Hope this helps. Please feel free to ask follow-up questions