Your ongoing tiredness and weakness could come from anaemia, a
thyroid problem, or a
vitamin deficiency. These are common and usually treatable. Skin that's darkened over time is worth mentioning to your doctor too, since it can point to the same causes. Your dry cough and chills over the last month are most likely a separate, lingering infection.
Next Steps
Get a CBC,
thyroid, and
vitamin D or
B12 test done to find the exact cause. See a general physician this week, since several symptoms together need one proper workup rather than treating each separately.
Health Tips
See a doctor sooner if you develop high fever, breathlessness, or the cough brings up blood.