Confused question???

For about 3months I have used glow an they havent been wrong about my period besides last month I started one day before they said I was goin to..no big deal well this month they said id start tuesday I think an here it is Thursday stil no period so I went in to the.period log an put in it was late so they said id start tomorrow(Friday) I took a pregnany test wedensday it was BFN well now my boobs are sore an the past two months ive gained abouy 15lbs which I just got a new boyfriend so I think its just cause im happy well now im starting to.think im pregnant you think im just to early to tell???