I was 38 weeks at the time so it might be different... but with my last pregnancy my water was leaking.
I thought I was being paranoid so I asked my OB and Googled (of course!) and what they suggest you do is lay down, naked from the waist down for a half hour. This gives the "fluid" a chance to pool up. Then stand up and if you feel it "gush" or trickle/flow, try it again. If it happens again, there's a chance it is your waters leaking and you need to be seen promptly.
BUT if it is his little guys, I imagine they could pool up and leak out as well. So I suppose you could lay down for a half hour and then when you stand up, put a pad or toilet paper underneath to "catch" whatever leaks out and give it a sniff, as silly as it sounds. They say your amniotic fluid has a "sweet" smell to it whereas discharge, urine and semen all smell different/distinct.