Posible po bang mabuntis kahit naka birth control implant? At nakakaranas po ako ng unexpected spot

Sobrang effective ang implant, like 99%+ talaga, kaya very unlikely na mabuntis while you're using it properly, pero yes may very minimal chance pa rin like sa lahat ng contraception. The unexpected spotting you're having is super normal sa first few months, a few of us had that din, kaya don't worry, it usually settles down after 3-6 months, pero if it's heavy or won't stop, better check with your OB just to be safe!