How to know if water broke?

I’m a ftm at 39+3 and for a while now (week or more), I’ve felt like I’m leaking something like when you’re on your period but initially nothing was there when I’d go to the bathroom. Frequently though my underwear have a wet spot.

It’s never enough to soak through but enough to be annoying and make me change them once or twice a day. I’ve been writing it off as normal discharge (although it’s just wet, no mucus or anything) and assumed it’d be more obvious if my water broke but I now I’m starting to second guess myself. Any advice or What have your experiences been with water breaking?