Brief Answer:
Long list of causes as your prevention is vague ma'am

Detailed Answer:
Hello ma'am and welcome.

Thank you for writing to us.

I have gone through your query with diligence and would like you to know that I am here to help. Myalgia (muscle aches) can have various causes, but taking your sex and the increased intensity at night into consideration, I have a few possibilities that I would like to list for your reference:

+Thyroid abnormalities: One of the most common causes for body pain in women; do you also have other symptoms like fatigue, weight gain, dry skin, puffy face, increased sensitivity to cold, thinning of hair, impaired memory, muscle weakness, etc.? Please get your thyroid profile checked
+Overuse
+Side effect of medications
+Some chronic conditions (e.g. lupus, polymyalgia rheumatica, etc.)
+Infections (viral, staph, etc.)
+Rheumatoid arthritis
+Strain
+Stress (e.g. repetitive stress injuries: usually because of daily routine or profession)
+Dehydration
+Anemia
+Fibromyalgia
+Rhabdomyolysis (serious)
and a few others.

But as you have mentioned that the pain is quite constant and has a fluctuating intensity, I think it is best for you to get elaborately evaluated for further management and relief ma'am.

I hope you find my response helpful. Please feel free to write to me for any further clarifications, I would be more than happy to help.

Best wishes.

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