it would probably be rare for
creatine to raise blood pressure. It does result in water retention, but that's in the muscle cells, not in the circulation. If it were causing the rise in BP, that would be a rare case.
OTOH, the creatine probably is the likely suspect. So, like everybody says, the reasonable approach is to discontinue it and see if BP goes down. That's not guaranteed, and you can't overlook the possibility of something worse, like kidney disease.