My girlfriend and I recently had sex?

On friday me and my girlfriend had sex we used a condom and pretty sure it wasn't ripped. That eek she was supposed to get her period she got it on sunday and has been bleeding but at differwnt times its not a little at at a time its kinda alo.again its at differwnt times we are worried that se is pregnant andis spoting does this sound like a period or spotting please help.we are worried.