Emergency room

I went to the hospital yesterday thinking I was having another miscarriage due to a decent amount of discharge coming out even though it wasn’t bloody or anything I wanted to double check because it just seemed like a lot all at once and they said everything is fine with my son and that he’s actually measuring a week and a half ahead! I’m supposed to be 15 weeeks today and the hospital said yesterday that it looks like I’m 16 weeks and 3 days! Has anyone else experienced this like I thought that was crazy and was kinda confused on how