Morning after pill

So my last period ended on Thursday 29th of August, and me and my boyfriend had sex on the Sunday but the condom broke, I went to the clinic 2 days later got the morning after pill, it’s now been less than 2 weeks since my period ended and I’ve already got another one!?

I know you can experience some bleeding from the emergency contraception but this is a full blown period with break outs and stomach pains.