I+had+my+period+on+6th+nov++on++27th+nov++i+had+sex+so+next+month++i+need+to+gt+my+period+on+6th+dec+bt+i+gt+it+on+3rd+dec+.is any chance be pregnant ?

Always a chance: If you miss your next period, please check for pregnancy. If negative it may take another week to become positive if you're pregnant. If you have regular 4 week cycles then you may have been well past ovulation when you had sex. Likelihood for pregnancy isn't high, but always a consideration when a menstruating female misses a period.