Period?? Spotting??

I started on cd 37, which is late for me. First day I noticed brown only when wiping. I didn't use anything that day or night. When I woke up the sevond day there was some brown in my panties. I decided to go ahead and wear a light tampon for work. I changed it twice that day, not due to it being full but it was very watery with brown streaks on it. That night I didn't wear anything again. I'm still having brown when I wipe, once in a while with a little pink with it. This is either the 3rd or 4th day. Is this considered a period or spotting? I don't know what information I should put into the calendar... please help!