Late while on BC 😰

Okay so I would have crazy cycles before so my Dr put me on the BC Pill. I am on my 2nd pack (30 day cycle) and today is my first day on the white pills when I'm supposed to start my period but I still haven't started. I am having the symptoms I usually do before I start (emotional, slight cramps, tired, sore breasts) and I was right on time last month and I know I still have half the day left today for it to come but before I start to freak out is it normal to be a little late even on the pill? There was a day or two where I might have taken the pill maybe an hour late this month but that's it. 
  I was sick for almost 2 weeks (about a week ago got over it all) with the flu and strep so was on Tamiflu and amoxicillin so could the meds have effected anything? 
  And I am sexually active but it's long distance so I haven't had sex since Jan 16th (after last period but still on the very last of my white pills/beginning of new pack) and we still used condoms. 
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