The shot

Gabrielle

So I’m on the shot and I have been for about 3 years. For a while I only had a period as my shot was wearing off, but since my last shot on August 2 I’ve been spotting or full on bleeding most of the time (I’ll have no bleeding a day here and there). Should I be worried? Do I need to call my doctor? Is there a possibility my shot isn’t working? Is my risk of pregnancy increased if I have sex on one of the few days I’m not bleeding??