... get on my period on the 2nd or 3rd inactive pill. I'm on my 5th one today and I havent had my period yet. I missed one pill but I took it with the next one the next day. My fiancee and I don't use condoms because we were both virgins when we met unless I'm on an antibiotic then we use backup until a week after I get my period.I havent been on a antibiotic for a couple of month so I don't think thats the problem. I don't see how it's possible but I'm still scared because I have had my period every other month so far. I did take prednizone for a couple of days, its a steroid I had to use for my asthma and I was on loratabs for a few days out of this month also. Could those be affecting it? Should I be worried?