It could be!!! I kind of had the same thing when I was preggo with my son. Around the time my period was due I had some light spotting although it was because me and my hubby had just had sex so I'm not sure if it would have happened anyways or not.
Good luck! I hope you get the answer you're looking for. Maybe run to the dollar store and get a cheap test? I ended up waiting until my period was a week late which drove me crazy! Hopefully you don't have to wait that long