HCG Blood Test Tomorrow

Period is a week late today. I tested the day before and the day after i was due and then 3 days after i was due with all negatives. Still no period..finally getting a blood test tomorrow to confirm if i have skipped a month or if im pregnant. Boobs have started to feel tender today, so maybe im coming on soon. Who knows, does anyone know how long it takes for your results from a pregnancy blood test?