First time mommy worried

So I’m about 6 weeks along. I’ve had pretty severe cramping the last week but it revolves mainly around my bowel movements. My HCG levels are rising and duplicating. I’m nauseous, exhausted and the sorest boobs ever! Today my discharge went from yellow to slightly brown. Please tell me this is normal? Any other ladies experience slight brown discharge with cramping but still have a normal, healthy pregnancy?!