Is the intercourse anus before the start of antibiotic use protected?

Good morning! Since April I have been taking vibin mini tablets, bleeding has always appeared. I've always taken them regularly. On Tuesday, a week ago, the last intercourse took place without additional security in the form of a condom. Today the doctor prescribed me a 3-day antibiotic Azitrox. It is true that I have not found information on whether azithromycin affects the effectiveness, but I prefer not to tempt fate and let go of intercourse even with a condom during the treatment period and a week after it. I wonder if this ratio from Tuesday was safe if I took the first dose of antibiotic today? I will add that I am now at the end of the 2nd row of pills. Today I saw a slight spotting on my underwear, I was scared that by a large amount of medication (previously I treated myself on my own) the protection could weaken. I do not know if I should take a break after this package or not? Please help