Late but negative

Sarah
I am really hoping to get some insight into my current situation. My husband and I have been TTC for about 9 months now and I am always regular, never missed a period since I stated having them. Since tracking my cycles back in November I have been either 27 days or 28, never anything different. Well today makes my 38th day cycle but I had a negative pregnancy test yesterday and this morning. I have not been feeling good the past two weeks, just no energy, nasusea and lots of sweating and hot spells. Has anyone every went through anything like this? Is it possible that I am pregnant? Any ideas ladies?