On the 13th of this month I had sex and he came in me, I have Implanon and it hasn’t failed me before but over the past couple of days I’ve had sore boobs, itchy boobs and I feel like the areola is a bit darker. My period tends to come whenever on this but usually it comes every 13 days and now its been about 18 days since my last one and it still hasn’t come so naturally I’m freaking out thinking I’m pregnant? Do you honestly think there could be a chance I am?