Nexplanon Questions

Hey! I have a few questions/concerns about being on the implant, and i need someone else’s opinion.

I’ve had my implant since March 2021. I had my last period about a month after. I just recently started spotting/lightly bleeding. It happens every time i have sex, usually a couple of days later. It can range from spotting to light flow & from light pink to dark brown/black. Just recently it happened out of nowhere a week after i had sex, not 2 days after sex per usual. what does this mean?

i’m always constantly anxious & think i’m pregnant because my boobs are always sore, and i bloat obnoxiously at varying times. one week i could be fine & the next i’m not. is this all just an effect of the birth control?