Help me

So on Friday while my mom was gone at a appointment my boyfriend came over mind you he’s older then me but we ended up having sex I guess we was so caught up in the moment being that it was my first time that I don’t know if he finished in me or what and my period is close like on the 4th I start and I’m kinda scared that I might be pregnant I never wanted to be a teen mom being that I have so many dreams and goals what should I do