What Does A BP Reading Of 90/60 Indicate?

I jusst took my blood pressure and got a reading of 90/60. I am on 50 mg Metoprolol and 10 mg Lisinipril daily. I felt washed out after working with hubby doing yard work (unusual) which is why I took the B/P to begin with. Is this reading daangerously low? My email is: YYYY@YYYY

Thank you.