Why Am I Experiencing Spotting But No Period After Taking The I-pill And Antibiotics For Tonsils?

Hi, my last period date was on 3rd feb which was completed on 8th feb, then on 11 & 12feb i had sex but immediately withing 48hours i took ipill. At that time Or even now I am consuming antibiotics for tonsils. On 25 feb i observed spotting but till now I am not having periods can u tell why it s happening?