Please Help! Am I Pregnant???

Ok so here's my situation. I started the birth control pill almost two months ago and I've never missed a pill. I spotted for about a week before I was supposed to get my period. My period was supposed to start 5 days ago but it didn't, so this morning I took a pregnancy test. It initially showed a negative result so I threw it away and forgot about it. But me being me I dug it out of the bin to check it again this evening and there was a faint blue line. Idk how I could possibly be pregnant, is it possible that something went wrong with the test?? Please respond. Anything is helpful