Period duration

How long does your period last? 
Earlier mine used to last 5-6 days (when I started getting periods) 
Then it became 4-5 days
Then I'd bleed for first 2 days & nothing on 3rd day then again bleed on 4th day
Now I only bleed first 2 days then it's done! 
Is this normal? 
P. S. I'm only 26