Implantation Bleeding or Period?

Hannah
So I am fairly certain I ovulated on Sayurday October 15th We had sex on the Wedneaday early morning and again on Saturday that week
My last period was 9/28 but I have a longer cycle typically (34-38 days) 
I usually ovulate later (cycle day 16-22)
  I have been using the AVA Braclet and it predicts my next period should begin Tuesday (normally is forms within 1-4 days of the predicted day on my apps) 
I haven't had. A positive pregnancy test yet. But  Today I woke up and notice a little spotting/discharge and then when I wiped I had very light pink/brownish spotting/blood and then just slight spotting since.
I wonder if this is my period or if it's too late for implantation bleeding.  
Thoughts?
Thanks!