Brief Answer:
needs work up and clinical correlation,

Detailed Answer:
Thank you for asking
Lower abdominal pain with lower back pain can be any thing. it may involve Gastrointestinal tract and bowel troubles like functional bowel disease etc may be behind this. It could be Uterine pain, It could be a urinary tract infection. could be kidneys. could be anything in lower hypogastrium.
Back pain is likely an extension of this pain. Its referred to the area usually. It could be due to disc compressions or muscle spasms.
Nutshell in order to comment better we need a little work up, a complete clinical history detailed assessment of genitourinary tract, some work up like urine exam, ultrasounds, blood count and some radiology to connect the dots.
Mean while take some muscle relaxants for the back pain. so me antispasmodics for the lower abdominal pain. Avoid lifting heavy weights. Increase fluids intake . Use fibrous and soft diet.
Get to a doctor and let them take care of you.
I hope it helps. Take good care of yourself and dont forget to close the discussion please.
May the odds be ever in your favour.
Regards
Khan

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