Should having brown blood just be the start of your period?

Around Monday it was light red and I saw some blood on the toilet paper that looked like I was on my period then I put on a pad. I changed it when I got home an on the pad it was just dark brown blood. Yesterday morning it was light brown spotting with a little bit of light red bleeding and then just brown blood nothing ever got heavier. Earlier brown blood again, light spotting and very very light red bleeding. I am not on birth control and I did have unprotected sex a couple of times I am also ttc.