Brief Answer:
Diet changes may be a cause.

Detailed Answer:
Hello dear, welcome Ask a doctor's service.
I read your query and here is my advice.

There are several conditions that can cause you constipation.
Most probable cause can be diet changes recent like using less fibers in your diet, less fruits and vegetables, less water more processed food, flour, diary products.
Lack of physical activity can also contribute to this problem.
Some medications can cause constipation as a side effect such iron supplements, narcotics, antidepressants.
You can write me if you had any of them recently.
Improving your diet can help you.
Using more water and fibers especially prune can help.
You can use laxatives such sena leaves

Hope I have answered the question.
Let me know if I can assist you further.

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