Hi, I was on birth control pill for a few months. I was taken off that for two weeks due to an injury that caused worries about blood clots. They switched me to the depo shot two weeks after I had been off the birth control. I started a period the week before I got the shot, and have been sexually active. I have yet to have a period since the switch. I have not been feeling good either due to stress, a bug, or I am concerned I am pregnant. Is there a high likelihood that I could be pregnant? I took one test 3 days ago, it was negative. I am just concerned.