Please help!! Early short period now spotting

Stephanie • Mother to a sweet baby girl born 14 October 2015 💗👑💗
Hi everyone,
​My SO and I BD'd on two of my highly fertile days 9/5 & 9/6...I ovulated on 9/10 with intense cramps. AF wasn't due until 9/27, but came on 9/22 and was very light, only lasting 2 1/2 days. I had nothing for a day, and now today and yesterday I have light tan discharge...very small amount on a pantiliner. Tested negative ?yesterday. Now I'm freaking out thinking I have endometriosis or PCOS or something. Any insight would be greatly appreciated. TIA. :)