If my due date is oct 27 could I have got pregnant feb 8

Yes, it would be possible. But keep in mind that due dates are not exact... very few women actually give birth on the due date. Since the exact date of conception is often unknown, due dates are derived from the first day of the last period or, on occasion, altered a bit after an ultrasound.

If this happens to be a situation where more than one person could be the father, and the encounters were close enough together, DNA testing would be necessary to know for sure who the father is.

Yes.

Sorry, didn't see Doula's answer.

Well my ovulation date was feb 5. and I'm 6weeks 1day today

Did you determine your ovulation date from the date of your period? Often this is what the online calendars will follow. While some women may follow that pattern, many others do not, and being off by just a day can make all the difference.

Most women will not know the exact day of ovulation unless they have had medical assistance to achieve conception. Some women will have a fairly good idea after monitoring their cycles for a time through the use of methods such as ovulation predictor kits or temping and charting.

Because dates of conception are not known for most women, you will have a window of several weeks at the end of your pregnancy in which you could give birth that would be considered perfectly normal. This is partly because some women will naturally ovulate a bit sooner than the norm, and some a bit later.

I can't be 6 weeks already if i.got pregnant on feb 8th

Please read what DoulaLC said again, very carefully.

You don't really know if you are 6 weeks and you don't know if you got pregnant Feb 8 (unless that was the only day for weeks in either direction you had sex). You haven't said how you arrived at an ovulation date. Doctors estimate based on last period \ and eventually somewhat on ultrasound.

I did have an ultrasound which said I was 6 weeks even?

Then discuss this with your doctor.
A woman who is concerned with the date of conception is usually concerned with the paternity of the child, and unless sex was many weeks apart, there is no way to establish that without DNA testing after the child is born.