How early?

Hey, guys because I’m a little scared right now and I’ve run out of things to look up, and run out of YouTube videos to watch.. I need advice from an actual person that I can talk to.. How early can you sense pregnancy symptoms? I read some girls feel tenderness in their breast, period like symptoms and fatigue as early as the first week after conception. it’s been almost 2 weeks since I last had sex I’m supposed to get my period Saturday and last week I was having really really bad and unusual pain where I would usually feel cramps it’s never happen to me before but I just told myself it was gas and now this week I’ve just been tired but I’ve been blowing it off because I work go to school and I have dance on Tuesdays and Thursdays and my boobs are tender honestly I’ve just been telling my self I’m tired because I’m busy and the period like symptoms are happening because my period is coming soon. Second opinion please (yes we used a condom but I kept slipping and when I saw him take off the condom it had a lot of cum in it so I’m really scared it maybe could have leaked?)