Pregnancy discharge

What is normal pregnancy discharge? I'm 39 weeks and my doctor asked me if I was having any discharge, which is dumb because I've told her I have been and how it's been making my underwear wet. I even asked if I could be leaking fluid and she said no. So anyways now here I am and it's got even worst. I can't tell if it's discharge, sweat, or liquid. Yesterday I was at Kohls with my mom and I could tell I was getting super wet down there. So I checked and couldn't see anything on my pants. But I sat down on a bench and when I got up there was a wet mark 🙈 there's times where it's going through my butt crack even. So now I'm worried I really have been leaking this whole time. I wear pads and they don't ever feel soaked though. And Every time I've been measured I've been right where I should be. So idk?