Mixed emotions

I started spotting three days ago. Not a whole lot mostly just there when I wiped and a little on a liner at times. It started of dark and now is bright. This is not my typical start to AF but since it was about that time I assumed that's what it was. Today is the day AF should be here and still this light spotting, so I took a test and it was positive. It was faint but there was defiantly a second line. Now I don't know what to do. I am excited to see that second line, but what does the spotting mean? I am too afraid to get excited just yet.