2 negative tests, one a blood, and missed period

hi everyone!
I am new here so bear with me. the thing is, i am almost 3 weeks late for my period and having crazy symptoms. my breasts are growing and sore to the touch, i am nauseous, constantly exhausted, and then the missed period. i missed 2 weeks of bc and may have conceived but i am so not sure. my mom says my hormones are off balance. anyway, i took a home test and it was negative, then a blood test which was also negative. i had spotting about a week ago, but that was it, no real period. could it be something bad? what should i do, if anything?
slightly scared,
LadyBri