Hello, and I hope I can help you today. It is unclear from your question how you are sure you are pregnant; did you do a urine pregnancy test? Pregnancy symptoms can vary widely between women and the most common sign of pregnancy is a missed period. If you have had a positive pregnancy test during this time, bleeding on and off like this can be a sign of miscarriage or an abnormal pregnancy. I suggest you see a GYN doctor who can measure the level of pregnancy hormone in your blood and perform and ultrasound test to make sure the pregnancy is developing normally. I hope I was able to answer your question and best of luck for the rest of the pregnancy, Dr. Brown