I'm getting a pregnancy test, if its positive what do I do?

I'm new but yeah I'm young, too young to be having a baby, my parents would slaughter me and my boyfriend and I don't want that My period is usually due around the end of the month to the start of the new month, so about the 20th last month my boyfriend and I had unprotected sex after protected sex, I told him to stop and he did, he assured me he felt not even remotely like he was going to finish However, this is the 7th, therefore I count my period being a week late what do I do? My boobs hurt, that's about the only symptom, everything else is normal I have a doctors appointment on Monday so if my period isn't here then, I'm getting a pregnancy test, if its positive what do I do? I'm way too young to have a child, I'm still in school for gods sake Please help me I'm really stressed out about this and I have been since the start of the month