What Causes Irregular Periods And Nausea After A Tubal Ligation?

Hello my name is Crystal, Im a 33 year old female... Had a tubal ligation done in 2007..Im having menstral problems... 2 weeks ago I had my regular monthly period... Then 4 days after I stopped I started my period again.. it started out light, but now it seems to be getting heavier, and with it Ive been nauseated so bad at times Ii end up vomiting... should Ii be concerned or let ir ride..