Leaking Fluid?!

Have any of you leaked amniotic fluid before? I am almost 33 weeks pregnant & have noticed that my discharge has changed to clear and watery. It is also accompanied by lower back cramping/pain. I know it's not urine because it happens no matter what & has almost no smell (but kind of reminds me of a semen-like smell, no sex for weeks though). I do plan on asking my doctor of course but figured I would see if any of you have experienced this before! Is this normal or not??