Hair fall, elbow darkness. Helpful?

No significant health problems. Everything is noraml. Recently too much hair fall since 2 to 3 months almost more than 100 hair follicles. Menstrual history irregular frm 6 months almost 50 day cycle. What tests r recommend?plz tell basic investigations if necessary. What I may be suffering frm. Wt normal, BMI within range. Unmarried, no other health issues. Iam trying to eat  healty food, having issue with sleep.  Got covid  almost 3 months back. No hospitaisation  ,cured with basic medicine. And elbow blackness frm almost childhood and  blackness on my toes on some area. Any creams helpful? Scrubbing done excessively for few times it became ever more black. Then I realized to do gentle scrub only. And I stopped scrubbing. Very occasionally iam doing scrubbing very gently. Kindly advise wat to do for hair fall, and elbow blackness