Ive been on birth control for 3months and i havent got my period yet. is my body getting used to the pill? should i be concerned about pregnancy?

Oral contraceptives: Most oral contraceptives are designed to have either a week off or a week of dummy pills with no hormones. During this week there is usually a withdrawal bleed. Sometimes doctors will manipulate the pills to have no bleeding for more than a month at a time. Please discuss with your doctor to ensure you are taking the pills exactly as planned. A pregnancy test may be comforting.

Ocps: If you haven't missed any pills then there is not a need to worry about pregnancy.