Ok, im a little panicky.

Ok, I was ovulating last Wednesday, (9th Nov) and had unprotected sex. I am not due on until the very end of this month so its obviously too early to tell if i was pregnant but yesterday i was bloated and had a little spotting. Today i have had a bleed, it is watery blood. I m really concerned because my periods never come twice in one month and i usually have heavy clots not watery blood. Please help. What could this be