Calf cramps- anyone relate?

Okay so NO ONE ever has the answer to this. So I get these calf cramps but ONLY when I’m pregnant. It’s always in the morning when I stretch out upon waking. I learned a way to stretch but not hold it long enough for the cramp to happen. But it’s not fool-proof. And when I say “calf cramp” I don’t mean leg cramps or sciatic cramps. I mean this EXCRUCIATING golf ball sized cramp right below my knee (top of my calf muscle) that causes me to writher around the bed and cry out in pain til it stops then I limp around with a golf ball sized knot in my muscle for a few days. does ANYONE have these? All the OB’s I’ve mentioned it to in the last 3 pregnancies (2017- this one) have just said “more potassium blah blah.” Yeahhh I eat bananas like a damn monkey. That ain’t it. But I’m looking for my fellow mamas that have experienced this.