probably pregnant

So, I had the talk with my mom and she ALWAYS tells me to not do stuff and I say that I won't to them, then I end up doing them (we talked about drunk girls and that night I went home SUPER waisted) stuff like that and she was like I don't want you to get pregnant and I was like I'm not going to, and that same day I has sex w my boyfriend and we didn't use a condom, even though he didn't cum in me the second we were done having sex, I started feeling weird, so he told me not to worry, that was exactly a month ago on the last day of my period (I'm not on birth control) my period is late 2 days, I've had a lot of mood swings, nausea, and I'm cramping a lot today...so I feel like I just got pregnant by irony, for not listening to my mom (I'm 17) someone please tell me if this has happened to you, I'm so scared