pregnant?

I lost my virginity to my boyfriend 4 days ago and I'm nervous. When we had sex he didn't go all the way in because it hurt too bad and it only lasted like 1 minute because I was in pain he says he didn't cum and I know he didn't but I know there can always be precum. Every since then I've been feeling nauseous but I've been looking up symptoms so I think it's just me being scared making me feel this way and even the thought of being pregnant makes me nauseous so I think I'm just being paranoid. Could I be pregnant?