AF late

Addie
I really need everyone's advice. I was supposed to get my period on Friday (2/3/17), I took a pregnancy test on Friday and I saw a faint line, today (Saturday 2/4/17) I look a test and it was negative. I have been very nausea and even vomiting lately. Also, I've been experiencing light cramping. 
1. Do you think I should take another test? If yes, when?
2. If I don't get my AF by next Friday do you think I should schedule a physicians appointment?
3. Any other suggestions or tips?