Light period 6 days early??

I'm not due for period until Nov 29 ( Sat) I started lightly bleeding on Tuesday and having cramps..the bleeding is on and off it is red and last night and today my left boob has been intensely tender! I've been nauseous for days now too. I'm not trying to conceive and I really hope I'm nit but does anyone think there's a chance I could be pregnant?... I bled for a little at beginning of last pregnancy with my first. I took hpt last night and was negative but is it too early too test...