Opinions please..dont know whats going on?

Ok I told myself I wasn't gonna ask but I want some womens opinion...well I don't think I'm pregnant and I'm kinda sure..lately I've been having bad headaches, my period was suppose to yesterday but hasn't arrived, so much clear discharge I thought it was pee but its not and sometimes it has white mucus in it, and by far the weirdest is I was at wrk and me and my coworker were saying we were hungry so I bought some pop tarts and I was starting to eat it, I finshed half of one and all of a sudden I felt full but less than 15mins later my stomach was growling..and ideas of what's going on?