Nausea at approx 3dpo, too early for pregnancy sign?

So, last night I was out to dinner for a friends bday party. Straight after I finished eating my dinner (spinach & ricotta ravioli), I felt nauseous. I ended up having to run to the bathroom to throw up, I didn't make it and threw up in the garden. It lasted for another hr or so, I had to leave early to take my boys home before I was too sick to drive. But, after we got home and I got the kids to bed, about an hr or so later, I was hungry again and I had a huge bucket of ice cream! My question is: do u think this cld be an early pregnancy sign or am I just symptoms spotting? Tia.