Need some advice and hope..

Sarah
Hi all! 
I need some advice. I Havnt had a period since November 2015. I've been checking for ovulation and have never received a positive. I received my first positive ovulation test on April 24 and 25. My DH and I did the baby dance both of those nights. I felt fine then I started to get really bad PMS. Cramps, mood swings, server lower back pains and a few zits. My period never showed up. It still hasn't. I did have some brown spotting yesterday 5-10. But that's it. I took a pregnancy test on 5-8 but it was negative. Do you think I could be pregnant? Is it normal to have heavy period sythoms with pregnancy? Could that of been implantation bleeding yesterday? Or would I have had that over a week ago? I'm new at this TTC stuff. And advice and/or insight would be appreciated. I feel really run down and tired. My mood swings are horrible. Feel like I'm going to cry or beat someone up at any given time. (Don't let that discourage you from commenting lol) thank you for reading!