Help please!!

Last week my boyfriend and I had unprotected sex. He didn't ejaculate inside me, but I know you can still get pregnant from pre-cum. This week I've been feeling this weird pressure in my lower abdomen, it feels weird to lay on my stomach, I've had gas and I have this feeling in the back of my throat which makes me feel like I'm going to throw up but when I try to all that comes out is a burp. Are these signs of pregnancy?