Low blood pressure

Jessica • Mama to 4 boys and our first little lady :) Evelyn Margaret 3/26/16
I've been getting headaches, exhausted, nauseous so I thought I'd take my bp to make sure it wasn't high. It's 90/50ish. I'm not sure whether this is my new pregnancy normal or to be concerned. I had hypertension last year due to stress (special needs twins got their diagnosis') and my bp was 180/120 so it weirds me out being so low. Anyone else?