How long after sex does the semen come out?

So this morning I had sex at around 10.30am, we used a condom but right now I'm not on the pill because my body reacted to it badly. So the only form of contraception was a condom, I've felt slightly moist down there all day (I did shower after sex) and just now I felt something come out of my vagina when standing up ready to get in the bath, it was a thin watery clear liquid. . It is now 10pm and just worried that what came out of me could have been semen. Am I worrying for nothing?