So confused.

So i had what i thought was a chemical pregnancy, i got four faints and 1 clear bfp last week. Then i had a 3 day light period that was 3 days late. And 3 more days of brown spotting. We just assumed try again next month but i took a dollar test and it looked like it may had a faint line but i assumed chemical or miscarrige or whatever happened i could still have hcg. But im starting to feel sick and tired like my kast pregnancies. And my breasts hurt so bad as well as my back. And still brown spotting which isnt normal for af for me at all. I usually have 4-5 days of heavy crampy hell. Now just 5-6 days of light bleeding and all this spotting that wont stop !! What should i do ?