TTC 5th month now :(

Hey y'all my names Shelby. Me and my husband have been trying to conceive 5 months now and always get that not welcomed negative. I have no health problems, don't smoke, drink, or am over weight. I'm 19. Well raised family for support and his family also. He's a auto mechanic, and he's 25. I'm a house wife, also in school. There's no stress. But I missed my period this month. I usually get bloated, sore boobs, and a couple pimples. I keep having off and on sore boobs, no bloatyness. Took 2 hpt last week, negative! :(((( I'm so confused. Can anybody tell me their story's? Or help me with mine?