I think I'm pregnant

I had a baby almost three months ago and I think I'm pregnant again. i think I had implantation bleeding again (I had that when I was pregnant before) but it was like a lighter brown color and it lasted one wipe. My smell is really messed up and I'm super nauseous. My mother in law is in the house and she was fine and now all of the sudden she's been getting nauseous and she was living with me when I was pregnant with the other one and was getting pregnancy symptoms like nauseated and having cravings. For example on the smells I gagged cause the heat smelled weird and the air freshner smells weird in the car and I used to love that air freshner... If my period isn't here by the end of the day tomorrow I might be pregnant... My period is always on time and is never late and I'm not having any symptoms of having my period like not enough cramping and all the back pain that I always have... What y'all think