Is Pregnancy Possible While Having Birth Control Pills At Various Timings?

I am currently taking tri-cyclin lo birth control pills, the 28 pack. I was about 2 hours late taking the third pill of my new pack of pills. I was also a couple of hours late taking the pills on a couple more occasions throughout this latest pack but I understand that the first week of pills are of the most importance. It is important to note that I have never gone 24 hours without taking the pill. The date of my last period was on the 15th of September and I started my new pack on the 21st of September. I also vomitted on the 23rd of September but that was well after 2 hours after taking the pill (also during my first week of pills). I also had a bit of diarrhea but it was more of watery stool when going rather than constant, frequent bathroom trips. I was also on the antibiotic Cefuroxime on the 24th of September, toward the end of my first pack. I just want to make sure that given all this information, I am still protected from pregnancy. Thank you so much for your time