Worried..this never happened to me before?

Ok..i have been spotting for 4 days on and off. Me and the hubby have been trying for over a year. My lmp was May 31st and i usually have a cycle of 30-36 days. Dont know when i ovulated b/c im irregular. June 17th was when i started to spot..this has never happened to me before, I dont want to go see doc b/c she is a quack and for other health reasons she told me to tie my tubes and put a guilt trip on me.."oh if you become pregnant and something goes wrong and you end up dying, you dont want to leave your child motherless do you?"...Yeah a real quack let me tell ya...but back to the subject what do you think could be happening?