What Are The Early Signs And Symptoms Of Pregnancy?

hi, well i had my last normal period on july 16-jjuly19.i was expecting my next period around augt 16, but nothing. i was begining to worry because i was not recieving my peeriod. than about a week and a half later i went to the bathroom and when i wiped i noticed that on the toilet paper there was a brown is liquid on the paper. for the rest of that day every time i went to the restroom and wiped, the same thing would appear on the toilet paper.i thought i was going to start my period, the next day i woke up and went to the restroom and noticed i was bleeding.i was relieved because i had started my period.but than around 7 pm that same day i stopped bleeding and have not bleed since.i have noticed that i have been feeling a little different. i have been having upper abdominal pains when i am sleeping at night. really sharp pains that i have never felt before. my lower back has been hurting a lot and i have been having frequent headaches. at on point my stomach was really bloated for about a week. and i have been dieting so i didnt understand why my stomach was getting bigger. it finall went down after about a week. i have also been getting lower stomach pain and really tender breast but still no period.i have also been having frequent heat flashes and cold flashes. i ttook a home pregnancy test and it came up negative.so maybe i was just stressing out about things. the weird thing is i have been loosing weight instead of gaining it, and have been going to the restrom a lot more than ofter.at times i feel like i have to go so bad and when i go to the toilet i cannot go.i i body tempature since last night has been very hot. i have been having a head ache in the back lower part of my head right above my neck. and my lower stomach feels swollen. it has felt swollen for a while. i took another test but still negative, and i still have not recieved my period. can i be pregnant?