plan b

I was on birth control and then I got off of it after April. whenever I got my period in may on the last day of my period me and my boyfriend had sex, the condom broke so I had to take plan b. I still haven't gotten my period this month should I be worried that I'm pregnant or is it possible my body is going to skip a period or two because I got off of birth control and took plan b and that affected my body. help?????