Aiyoo don't worry so much lah, high cervix is actually quite common especially early on and boleh change as pregnancy progresses, a few of us had this and doc just monitor je to be safe, nothing alarming what. Best thing is follow up at your 23-week scan like doc said, and if you're really anxious in between, boleh call clinic and ask doc to explain more details about what exactly they're monitoring for, so you feel more reassured kan, sometimes just understanding the reason behind the extra scans helps a lot lah.