I am Dr. Arun and will be helping you today.
I am sorry that your question was unanswered for long.
An ovarian issue like oophoritis (infection / inflammation) would cause tenderness in lower abdomen. Your symptoms can also be due to;
1) Ureter stone (tube connecting the kidney and bladder).
2) Back sprain
3) Pelvic inflammatory disease.
Following investigations would clinch the diagnosis;
a) X-ray abdomen
b) X-ray of the lower back
c) Ultrasound of abdomen.
You may take Ibuprofen meanwhile.
Please feel free for your follow up questions.
I would be happy to assist you further, if you need any more information.
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