What just happened???

So I worked myself, I am 26 weeks pregnant and so the horny-ness is extremely bad. I used my vibrator, which I always do. But this time something happened that has never happened during masterbation or sex with a man. I had a bunch of discharge after I came. My bed sheet looked like I peed on it, I know its not pee... but like I've said it's never happened, what could it be?