Please read this. I'm going crazy over these symptoms!

Hi! I've written on here a couple of times before, and I'm going crazy over all of these symptoms! :o) Ok, first of all, my breasts are very tender at certain times. they hurt all of the time, but some times more than others,. i have a "full" feeling right below the belly-button, my lower back hurts certain times, and sometimes i'm really hungry, where i eat everything in sight. and sometimes I'm very full where i won't eat anything. Some days I sleep all of the time. I got my period, but it was only heavy for one day, and lasted half the time it usually does. I had brown discharge a little after that, and I've never had that before. I took an hpt, but i think i might have messed with it before i was supposed to, because i got a second line in the circle, but it was horizontal, and not vertical like it was supposed to be. Oh, yeah, this is really bothering me: i get twinges of pain sometimes like a cuple of inches under my belly-button,to the right and to the left. I KNOW im not imagining it. and if i take a long walk, it hurts in the same place, the kind of hurt like after you drink a lot of caffine or something. but mostly when I'm just sitting there i get twinges there. PLEASE respond to this and tell me if you think I could be pregnant. thank you guys soooo much! you're a great group of people.