I am currently 4 days late. i was taking antibiotics for bronchitis. can they cause me to be late. i have nausea, headaches, im tired/sleepy, cramps.

Pregnant?: You can get home pregnancy test kits from your local pharmacy. Any illness like bronchitis (for which antibiotics are generally useless) can alter the menstrual cycle, so you may be late on that basis.

Yes: Both antibiotics and illness can interfere with your menstrual cycle. Sounds like it is probably on its way but you may not get your "normal" period this month.