Spike in blood pressure?

As
I've had super low blood pressure the whole pregnancy.... Two weeks ago I was 112-71. My lowest was like 98-67. I've been soooo happy about it. But today I found out I've only gained half a pound in two weeks (abnormal for me as well) and my bp was 136/88.... It's NEVER even been 120/80, the normal. This is a big spike for me. My office doesn't get concerned until 140/90, but I am worried... Can someone help ease my concern?