HELP! IDK?

So I had sex with a guy a couple weeks after my period nov14ish I took a test 6 days later it said negative. I then had sex again 2 weeks later and I haven't gotten my period that I was suppose to get Dec 6. I haven't taken another test because I'm not sure if the first one I took was even accurate because I might have taken it too soon? I'm lost and don't know.