Creatine levels low at 15.5 weeks pregnant

I did blood work the other day and am a little concerned. I’m 15.5 weeks pregnant and my creatinine levels were low at .55/mg/dL. Says the normal range is .70-120mg/dl. My bun was also low at 8. Says the normal is between 10-20. Anyone know anything about this? Do levels get lower during pregnancy? I’ve never had this be abnormal before. I will call my doctor tomorrow about it I was just curious if any pregnant women also had low levels of creatinine. Thanks.