Morning after pill

Me and my husband had unprotected sex on the 24th of MAY and within 24 hours I took a generic morning after pill it was Labor Day Half of the pharmacies was closed due to a holiday so at target I found a generic Plan B, it's been 10 days and I never get my period no cramping or spotted  or anything?  The other day I got a fever? My next cycle is on the 6th. Is there a difference between the generic Plan B?