Water breaking or peeing?

Last night I had unprotected sex with my SO,and as you know the night of and day after sex the sperm leaks out. Well I threw up an hour or so after waking up due to extreme hunger (always hungry In the morning) and afterwards my underwear was soaked and when I wiped there was a clear liquid. How am I supposed to tell if my water broke? I'm 19 weeks and this is scaring the crap out of me