Is this normal or what??

Ok my last real period was on December 18th ... I got something that i thought was my period on February 10th and it only last for a day.... i only had to use like 2tampons and then it was more like brown discharge......can that be counted as my period??? also im never late so i was freaking out before but then i got that brown discharge that i thought was my period until a couple days ago i didnt think i was pregnant but then i have had really bad heartburn for the last 4 days and ive been sleeping till 1 three days in a row... it's weird for me cuz i always get up at 9ish just like clockwork but now my back is hurting like no other and i havent been able to eat much since two thursdays ago because i would get really sick..... i have been having a lot lately unprotected but do you think that was my period and am i experiencing pregnancy symptoms or no??