Is A 9-day Delayed Period After Taking Progyluton Tablets In January Normal, Especially With A Negative Pregnancy Test?

I took progyluton tablets in january for 21 days after my periods finished. From January 8 to january 28. My periods date was 29 and I got periods on january 30. But in february, I got no periods. My periods are delayed by 9 days. Still no periods and my pregnancy test is negative.