only brown blood!

Camryn
Last month I only had brown blood it was very very little but it lasted for 5 days (I had sex 2 week before this happened) so I took a test and it said no so a week later I still hadn't started so I took another test and it said no so basically I only had brown extremely light blood that month.....
This month I had the same 5 days of light brown blood but I still have a few more days until my period is supposed to start but I have no idea what's wrong with my body I have no pregnancy symptoms I'm just a little stressed I guess but has this happened to anyone else before? is it normal? Should I retest for a third time? Send help!?!!!?