is it possible to get pregnant after a tubal ligation?

hi i had a tubal (cut and tied)6 years ago i had my period on the 11th of thismonth but a week after i stopped i have been having lower cramps
sick to my tummy.lower back pain n my nipples are very tender and gaining weight.im not due for another 11 days but should i be concerned?
thank you for your advise :-D