Can you get pregnant even if your tubes are tied?I feel like I am please help!

I just had my tubes tied in May after giving birth to my second child,and my period has been late by a few weeks,off and on since then.But this time I am over two months late is it possible to become pregnant after having your tubes tied?I feel like i am pregnant but dont know i am to scared to find out cause I might be wrong...please help me!!!if you have any advice or anything on what to do can you help let me know?
Sincerley Carolyn