Ello. I'm 22 Year Old. I Had Intercourse 2 Months

ello. I'm 22 year old. I had Intercourse 2 months and 3 weeks back and had my periods start the next day, right on time. Everything was normal, so i didn't think twice about it. Then a month later, i missed my periods. I'm irregular at times, so i didn't get worried. When i was about two weeks late, i took a pregnancy test, which turned out to be negative. 10 days later, i took another one, again negative, and then a third negative a week later. When it was over two months, i went to see a gynecologist. She gave me Modus-10 for a week and said that periods would begin 4 or 5 days after i finish the medication. It's been a week since i finished, and i haven't had my periods yet. As i said, it's been two months and 3 weeks since i had my last periods. What does this mean?