Teen pregnancy

I'm almost curtain I'm pregnant. I lost my virginity last Thursday, although he used a condom, it could've split. I've been getting pregnancy signs: breast tenderness, back cramps, tiredness. Lots of people say you don't get those signs that early but I can tell you they are real and I've never experienced these pains before.
I don't know if I should tell my mum or wait, please help me I don't know what to do