Not Normal!!

Since Around thanksgiving I started to have mild nausea off & on & that's what lead me to get a pregnancy test. Took it about a week ago on a Sunday. It was negative. Still been having mild nausea since then but not everyday. So my next cycle according to blow was dec. 6th, I started spotting Friday night b4. Saturday & Sunday I bleed by Monday my cycle was starting to leave jus spotting that night very little spotting. My cycle has never stopped on the 3rd day. My cycle has always been 5 days my ENTIRE life. I feel like that's not normal to me given my past cycles.. What could this mean?! I have a doctors appointment Thursday maybe they'll be able to help...