period so short? is this normal?

Jasmine

For the past two months my period has only been two days. Is that something that’s normal? I am on birth control for about 4+ years now and never have I had a such short period with little or no blood. I haven’t switched my birth control same one. I do get cramps and nausea with dark blood the first day and by the second day it’s blood in the distance and by the third day it’s gone.