Hoping for some answers..

Hey ladies, just a little bit of a short back story.. This is my 4th round  of clomid. The first cycle I did not ovualte, but I was successful in ovulating these last two cycles. I am currently in my fertile window, and I have been taking opks. They have been all over the place, but last night I did have a little bit of ewcm, which I took as a good sign. Then a few hours after, I begin spotting.. Very light red to brown. I have been having VERY VERY light spotting today just when I wipe. I was just curios to see if anyone else has experienced this, or may know the cause.