period lighter then usual brown dark blood

Usually my periods hurt so bad! They are usually really heavy and i get bloated and horrible cramps. My boyfriend and I had sex thursday march 7 and we used no protection he also ejaculated and put it back in right after. And 11 days later i had A very small amount of dark brown blood. My first days of my period are usually really heavy right off the bat like small clots and everything. But this time it was barely anything. It got slightly heavier but not even enough to fill my pad just a smudge of dark brown. It has been a day and it's still sorta happening its on and off. I have no symptoms of pregnancy besides one really bad head achee and i am extremely exhausted with bad bags under my eyes. Nothing else. Am i pregnant or is there something wrong? Please help

[ktsweet95]

Also i took a pregnancy test yesterday afternoon and it came out negative.

[Rissa14]

Sounds like you are having a weird period. Implantation lasts 2-3 days and is usually pink, red or brown staining.

[ktsweet95]

Today is the second day and now it stopped again.