Hello. I Had My Last Period On 16-nov And Now

Hello. I had my last period on 16-nov and now My period is 2 days late, Ive got a pinkish discharge on wed and Thur of last week accompanied by slight cramps followed now by spotting. In addition have on and off back ache in my lower back and loss of appetite. I did a HPT last night and it was negative. I don't feel pregnant at all. Please advise.