Before I start - I know the only way for me to know if I am pregnant is by taking a test but it's too early for me to take so I wouldn't know yet.

I had my period last month, but this month I have been having a weird change to my body - my bf thinks I'm pregnant. I been getting nauseous in the car, in the supermarket and feeling extra stomach sensitive. I am also eating a lot and not feeling full (note that I am skinny af and have a hard time to eat normal sized portions). We did have unprotected sex during my fertile window. Now.. I just wanna ask, would it be even possible to have these signs when I would be at maximum one month pregnant? Wouldn't these signs come later on like 3m+ and are these common signs?