The patch.

Last month, I was out of town for a week (period week of my birth control) the following week I was supposed to continue the patch as directed, but I didn't. I skipped a week. Started it again as soon as I got another prescription. The entire month I have been cramping B A D & my period is late. Could these symptoms be from the birth control? 
Ps. I haven't had sex in over 2 months.