what are the possibilities of getting pregnant with tubes being tied

Hi,I'm. 27 years old and have two children after having my last one who is six now I got my tubes tied. Since then i've met a wonderful man and are getting married and were wanting just one more together. My period was only late b a couple of day's. But mind you with both of my two pregnancies. I had a period which was a regular one all the way up until I was 7months along. I have been so emotional and been having mood swings along wa little bit of nasuea and am always so tired nd feeling drained. Could I be pregnant or get pregnant?
someone please help!