The first figure is the pressure when your heart beats, the second is the pressure between beats.
If they're close together, it means there's not much difference in pressure between beating and not beating.
Your value is VERY low, do you ever feel light headed if you get up too quickly?
120/80 is normal. I've never seen anyone with pressure as low as yours. I would get it checked out, just to be sure. Just becaue you feel fine means nothing. My dad feels fine and he's obese with type 2 diabetes.