I Was Just Today Told That I Have Chlamydia. I

I was just today told that I have chlamydia. I am a 20 year old female, and I would have been infected about 2 weeks ago. I was prescribed zythromicin and am allergic to arythromicin so I want to take the medication on a day when I have the time to monitor myself in case I get an allergic reaction. I am going out of town this weekend and was hoping to start the medication on monday. However, will there be serious negative consequences if I do not take the medication immediately? Thanks.