Hi. I'm Not Sure If I Can Be Helped But

Hi. I'm not sure if I can be helped but here it goes. My husband and I just recently decided to have kids and I stopped taking my pill in the middle of my pack instead of finishing my pack. We had sex the day I stopped my pill which was last Friday. On that day I still had two weeks until my expected period. I was ovulating. It's been a week since that day and I got my period on Monday but it started weird and it was reddish brown in color and then it progressed as normal and lasted four days (ended yesterday). I wasn't supposed to start my period until next weekend. Could I be pregnant? Every test I've taken over the past week has been negative. But I've been acting weird and having migraines and breast tenderness and mood swings. As well as urinating frequently and not liking foods I normally love. As well as on and off nausea. Any advice would be great.