Is this normal for taking plan b ??

So my period ended the23rd of feb , I had sex unprotected feb 24th and took plan b like four hours after I had sex . I had little to no side effects except I puked once about an hour after I took it ... fast forward to yesterday feb 28th and I got my period . Quite heavy and I still have it today ...

I knew spotting was a side effect but I didn’t think a full blown period a week after my last period would happen ...

Is this normal ? I’ve never taken plan b before so I don’t know if it is or not