It really depends on what kind of antibiotics they are, antibiotics take away the effects of the contraceptive pill so just remember while taking them that you are not protected, but seeings as you didn't have intercourse during that time you won't be needing to worry about pregnancy. As for whether or not it can delay your period, like I said, it depends on what kind of antibiotic it is, have a read of the instructions that came with the pack, if you are still unsure you will need to ask your doctor if you still haven't got your period in the next few days.

Take care...

.::suzy::.