Can you get pregnant while brownish blood comes after period?

No: Brownish blood means old blood which is probably just resolving old menstrual blood. You typically ovulate 14 days before your period, so if you have a 28 day cycle, you ovulate on day 14 or day 16 during a 30 day cycle. Day 1 is considered the first day of your full flow. So unless, you have excessive long periods, you should not have ovulated during this time making it difficult to get pregnant.