Brown discharge?

Tanis • Don`t wanna get her pregnant
Next week will be my first period off the pill in years.
I also had sex 2-3 times abou 4-5 days ago.
We used the pull out which I know is not reliable, however I was not ovulating. Around 3-4 days after sex, I started getting a small bit of brown discharge. Now, day 5 I am still getting it. 
My period is in 5 days, could it be implantation bleeding or is it too soon?
I feel like my body could be reacting to sex because I haven't had it in months, or could just be preparing for my period soon.
Thoughts??