Help, I think I'm pregnant?

Rachel • Working on forever with my ever after. :)
So, I recently had the mirena removed in December 2013 and was put on the pill. I had a period in January and was due for it February 10th but I never arrived. Tomorrow will be three weeks late, last week (Tuesday and Wednesday) I had brown spotting but then nothing. I haven't taken my pill since February 21st just in case and on the 22nd and 27th we had unprotected sex. The last test I took was on valentines day and it was negative. I go tomorrow for a blood test from my obgyn. What do you think, would I be pregnant?