I got shot on july 29th of this year and i started taking antibiotics now my period is late?

Maybe unrelated: A woman who was normal on her periods and then stopped having them, can be evaluated by an ob-gyn doctor to see if there is a problem. The doctor will likely repeat a pregnancy test. If a woman only missed one period, there might not be a problem. Vaccinations and antibiotics aren't expected to alter periods. A primary care doctor can look for other medical problems that could stop one's periods.

Depends: You need to see your OB doctor. Trauma and surgery can cause menstrual irregularities but this is a bit long. Pregnancy is a possibility always for missed periods.

Clarification?: You got shot (like a gun) or got the shot. I think you mean you got the shot on 7.29 meaning depoprovera. If this is what you mean then missing periods is exactly what you would expect. Depoprovera shots cause most too miss their periods in fact that is a feature most users find very attractive.