Your blood pressure is too low. This site will tell you what the problem probably is. Time to contact your Doctor.
is blood pressure 101/57 okay?
The link that Rooster posted is a good one.
One of the statements in the link is " Usually a blood pressure under normal is harmless."
I once asked my doctor many years ago if my blood pressure was OK.
He replied, "Let me worry about that."
The point I'm making is that letting a doctor evaluate your blood pressure relative to any symptoms or other related problems that you may have is the best idea.