Late period neg tests

So I'm almost 2 weeks late on my period... And I've taken a few tests. All neg last time we did anything was weekend of October 24th  could I be pregnant and it's just not showing up yet on a test or something else? I haven't been all that stressed and the only other explanation is my thyroid problem I have (I haven't been takin my meds no insurance to get back on them but when I wasn't taking them a few months ago my periods were still normal) what's wrong with meeeeee?? Ugh!