Could I be pregnant? Please help

hi everyone thank you for taking the time to read my post.. I have been trying for a baby with my hubby to be and I have been having symptoms of pregnancy such as sore breasts ns feeling sick, I was due a period 4 days ago but i got nothing but yesterday I woke up with light pink discharge which then went into brown and a dark red colour, it lasted one day and has stopped today, just light brown discharge (hardly noticeable) on the pad, was this a period or implantation bleeding? Very confused, I took a test a few days ago it said negative but maybe I took it to early? Fingers crossed! Also very bloated!