Am I pregnant

I had my period on 11/05/2018 and I am also regular. I had constipation and I was feeling forgetful a lot last week. I also bleed on 12/03/2018 for about two to three days but the first two was like normal period and got lighter after that I got a pregnancy test on 12/08 it was negative. I am so confused if I should test again or should I wait until end of December 31 to see if af is going to come. I am worried I have a bit of sore nipples starting on Sunday 12/16/18 i think If i am pregnant today will make me sick weeks. Did anyone experience bleeding like that and got a positive pregnancy test please help.