I've been hospitalized five times in five years for blood pressure issues. Today I'm doing pretty good, thank the Lord.
A bp of 135/85 isn't bad. Everybody's different in that regard but a diastolic (the lower number) of 85 over a period of time isn't life threatening but it's not the best number to go around with for a long time.
If your blood pressure has a wide variation between laying down, sitting and standing then it might be simple dehydration — a person might regulate it with more water during the day and at night.
However, SEE A DOCTOR for these things. I had stage 3 cancer and did not know it — a doctor helped be realize there was a big problem and seeking the answers saved my life.
My BP seems to be related to sodium intake. I just can’t cook all meals from scratch, and thus end up buying frozen foods ready to eat after microwaving. This is why I mow my lawn on hot days. Sweating gets rid of lots of sodium from the body. I guess my kidneys are programmed to save sodium.