I just don't know why you think that's a low BP. You seemed to indicate you may have been experiencing some symptoms. But haven't disclosed any that I've read. And maybe you shouldn't here, but do let your doctor know.
If you are getting healthier from both exercise and eating better then I think what ever use to be your normal BP when less healthy would get lower. My diastolic has gotten lower over the years that I've been cycling, but I don't know that is from the exercise, old age or other heath issue. Frequently at home and resting it's 57 or less and the upper systolic is 100 - 115 most any time.