Scan 1.8mm 4-5 weeks <3 ????

Abbie • Pregnant with baby #1 so excited!!!
Hi everyone!
​I had my scan today and they saw a 1.8mm sac until 2mm they cannot confirm that it is a gestational sac! But they pretty much did confirm that's what it is :) I'm so excited! I'll be having another scan next week! Anyone else ever had a first scan with the sac this small? I'm only about 4-5 weeks pregnant! ????  my hcg at the moment is 274 and I'm going to have my hcg taken again tomorrow. Anyone else had a scan like this or in the same boat? ????