2 missed periods negative tests!?

so I have skipped 2 periods....my last was Jan 26.....taken at home test, took pee test at the doc, blood test, HCG quantitative test and had thyroid checked, no PCOS, no change in meds getting married but not stressed enough for that .....and all come back with NO BABY.

Symptoms: night sweats, sore boobs/nipples, nausea, constipated

Thoughts? I mean nobody can seem to figure out what's going on....is there really a chance that I could be pregnant and just not showing up or something sinister here, Im losing my mind