the only way to know for certain is to have a dna test when the baby is born or during the pregnancy. i am moving this to the pregnancy forum as i do not know where it best fits.

no, it's very unlikely.
for a due date of nov 27 the most likely date of conception is March 6th.
that is to say sexual activity of the 5 days prior to and including march 6 are the cause of this pregnancy.

If you definately did not have sexual relations with her between Jan 13 and March 14 then you are unlikely to be the father.

however you state you got back with her on march 6th if you had sex around this time (ie before march 14) then you are a likely candidate for the father.