Late period

Updated Okay, I’m 8 days late and I’ve taken two pregnancy tests both negative. One was regular line one and the other digital both negative. I’m on birth control and use condoms and I’m freaking out because I’ve never been 8 days late. About a week ago the dr had me on a steroid pack (medrol pack) so I wonder if that would delay it? Also I have never missed a pill and it’s a combo pill. One day I accidentally doubled up on my birth control and took two thinking it was a different day of the week. However I continued to take my pack as directed and never missed a pill! Update 3rd test negative as well 8 days late thanks for your comments :) it prob is my birth control messing my cycle up