Could I be pregnant?

Hey everyone! I just had my handsome baby boy 3 1/2 months ago and at my 6 week appointment I started the depo shot. They said after 2 weeks if we had unprotected sex it wouldn’t be that big of a deal because I’d have a very slim chance of getting pregnant again. Looking online, everything I’ve seen says a month. My husbands condom broke around the 3 week mark of my shot and the last few days I’ve been feeling incredibly sick, irritable and tired. I don’t know if it’s because my baby is starting his sleep regression or if it’s because I could potentially be pregnant. Any one who’s gotten pregnant on the shot or has experience, please help!