I had my tubes tied april4 2013 n now i'm having headaches and light bleeding with no pain could i be pregnant?

Doubtful: If the Tubal ligation was done correctly, you would NOT be pregnant.

Tubal and pregnancy: So, there is a possibility. Tubal ligation has an excellent birth control rate, however, it is not 100% (nothing short of removal of the uterus and ovaries has a 100% success rate). The problem here is that if you do get pregnant, you have increased risk of complications - tubal pregnancy being at the top of that list. If you suspect you're pregnant, see your doctor. Good luck!