birth control

Anyone else taking the Mylan birth control pill and not getting their period? I just got switched to this pill and I have no idea if what the affects of this pill is, any help or advice would be greatly appreciated!! Also I have NEVER been late on my period, I was supposed to get my period on the 18th of December and I have not gotten it, I've been taking pregnancy tests every morning and get negatives. I also just got diagnosed with Crohn's disease and am on Prednisone and I asked my G.I specialist if the steroid pills stop your period and he said no but it makes your periods irregular.. soooooo any advice and help would be great!