My husband had a vasectomy but am I pregnant?

In June of 2006 my husband had a vasectomy. He did not go and get checked afterwards to make sure he had no more sperm count. But I have not had to worry about pregnancy since then. I am never late for my cycle and come on every month for 4days but this month I came on for only 2 days. Everytime I eat I never feel satisfied or have that full feeling. What do you think?