Periods delayed for a month. Pregnancy?

Hello, Me and my fiance had a sex on 30th November, and her periods got over around 25/26th November. We used protection, however during sex she felt something torn in her body, seems that the vagina hole got slight bigger/stretched, and also she cummed for the first time. We also double checked the condoms and they were not broken After that we didnt had a sex till now, but the problem here is, she didnt got her periods in december and today it is 17th Jan, still no periods. We tested morning urine pregnancy test thrice (twice 3/5 days back and once like a week or 2 weej before) and all test were Negative. We tried eating papaya, pineapple, but nothing worked fine to get periods. If there is any solution or something do let us know and also is there a chance of pregnancy? Thank you.