No period

Patient: Hi i have been on the evra patches fpr the last 2 years and ive now had a reavtion to it. i went to seey gp and the told me to stop the patches and to take the pill. i had finish my 3 week patches and i syaryed my week free on thursday and i went to the gp the next day and i was told to take it from that day which i have. i was told ot takes fove daus to work since then i should have started my perod because of the patches could it be of the rigevidon pills