I was worried about this as well, my pantyliner is wetter than usual and there is no smell, it's definitly not urine.
I was told amniotic fluid smells like bleach and sperm? But I also read it smells very sweet.
I was also told to see if I'm always "leaking", because urine you can hold in, but I'm not going to sit on the toilet and wait for a drip to come or not. I could be leaking drops every now and then.
I bought a pad that changes color if it's amniotic fluid, but I know they're not 100% reliable. The color did change but not to what it's supposed to be if it is amniotic fluid. I have no idea.