Pregnant or not

I am really confused and dejected right now. My husband and I are not actually trying for a baby yet but eventually. So it was in the end of September when we did it, I had my periods in October on time, then a few days later I had some rather weird bleeding, it wasn't pink but it was almost like a light period, which continued for a couple of days. At that point I believed I must have mkscarried or something. We had protected sex during the end of October and now it's been three days since I have missed my periods. I did take the pregnancy test keeping my hopes high but the test came back negative. I would probably wait until end of the week, and take the second one if AF doesn't visit.